Friday, March 24, 2017

Protestant Theologian Carl Trueman on Catholicism as the Default Position

In my account of my conversion to Catholicism, I mention that one of the main things that led me in that direction was coming to realize that the Catholic position is the default position.  What that means is this:  Protestantism broke off from the Catholic Church.  Christ founded his Church, and he commanded its members to obey their shepherds and preserve the Church's unity.  Therefore, unless Protestants can provide a good reason for having broken off from the Catholic Church, their movement is rebellious and schismatic and a violation of Christ's commands.  The burden of proof is on Protestantism to justify itself.  If, in all other respects, the evidence for Catholicism and Protestantism were exactly the same, we should choose Catholicism.

In an oft-cited quotation, Protestant theologian Carl Trueman makes the same basic point.  The quotation comes from a book review of a book by Mark Noll and Carolyn Nystrom asking the question, "Is the Reformation Over?"

Every year I tell my Reformation history class that Roman Catholicism is, at least in the West, the default position. Rome has a better claim to historical continuity and institutional unity than any Protestant denomination, let alone the strange hybrid that is evangelicalism; in the light of these facts, therefore, we need good, solid reasons for not being Catholic; not being a Catholic should, in others words, be a positive act of will and commitment, something we need to get out of bed determined to do each and every day. It would seem, however, that if Noll and Nystrom are correct, many who call themselves evangelical really lack any good reason for such an act of will; and the obvious conclusion, therefore, should be that they do the decent thing and rejoin the Roman Catholic Church. I cannot go down that path myself, primarily because of my view of justification by faith and because of my ecclesiology; but those who reject the former and lack the latter have no real basis upon which to perpetuate what is, in effect, an act of schism on their part.

Monday, March 13, 2017

Catholicism and TULIP

As a Catholic who is a former Calvinist, I am very interested in the relationship between various Calvinist doctrines and the Catholic faith.  I've always had a particular interest in the Calvinist doctrines concerning predestination and efficacious grace.  I remember back at the very beginning of the year in 1997 when I first came to understand and be convinced of what I then (and for many years afterwards) called the "Calvinist" doctrines of grace.  I always knew, as Calvinists profess, that these doctrines predated John Calvin.  The doctrines of grace had been passed down through the tradition of the Catholic Church for centuries before the Protestant Reformation.  They were articulated in Scripture, apparent to a great degree to reason (at least parts of them), and worked out by the Church (and particularly by the great St. Augustine and his followers) in the Pelagian and Semipelagian controversies of the fifth and sixth centuries.  Calvinists, over the years, have come to be fond of summarizing these doctrines using the acrostic TULIP--Total Depravity, Unconditional Election, Limited Atonement, Irresistible Grace, and the Perseverance of the Saints.  You can find here a brief, typical Calvinist explanation of the TULIP doctrines.

Of course, ever since Calvinists as such came into existence at the Protestant Reformation, Catholics and Calvinists have naturally been at odds with each other and highly suspicious of each others' theology.  This is not surprising, seeing that the Protestant Reformation was a rebellion against the Catholic Church and the establishment of an alternative tradition(s).  Judging from my reading and experience, it appears to me that Catholics and Calvinists have had a perennial tendency to misunderstand each others' points of view regarding the doctrines of grace.  I find this sad and irritating as a person who has been on both sides and who believes that these traditions have much more in common than either tend to perceive or admit.  For this situation, there is blame to be had on both sides.  I see myself as having a calling to try to help create a bridge of understanding between the two traditions, and what better time to be working on this than the 500th anniversary year of the Protestant Reformation.  I want Catholics to see that most Calvinists' beliefs on these matters come, to a great degree, straight out of the Augustinian and biblical tradition of the Catholic Church and are not to be feared but to be celebrated.  I want Calvinists to see Catholics not as betrayers of the doctrines of grace (which is how many Calvinists in fact see them) but to see the Catholic tradition as one that has preserved and which honors these great biblical and Christian doctrines--indeed, even more, as the tradition in which is found the true home and context of these doctrines.  Martin Luther once said that the doctrines of grace were the "essential issue" of the Reformation, the "hinge upon which all turns."  He believed that the Catholic Church had betrayed these doctrines.  If he was wrong, perhaps it is time for Protestants to consider whether they might have left home to preserve something that had been there all along.  And lastly, I want to help Catholics to better understand this aspect of their own tradition so that they might treasure it more highly and receive its blessings.  Calvinists tend to spend a lot of time thinking about these matters, but the average Catholic does not.  He knows that the Church emphasizes salvation by the grace of God, but he is extremely fuzzy when it comes to what that means in terms of predestination, the efficaciousness of grace, and the other issues addressed by the TULIP doctrines.  I want to help Catholics be more aware of the rich treasures their tradition holds in these areas.

EXAMINATION OF TULIP

What I want to do in this article is to examine each of the TULIP doctrines.  To some degree, it must be admitted, Catholics have been right to be wary of Calvinist articulations of these doctrines, for not all Calvinists have understood them in a sound manner (from a Catholic point of view).  But Catholics have too frequently gone too far and painted all Calvinists with a broad brush, attributing to the tradition in general the errors of some, even though, so far as I can see, the most classic manifestations of this tradition (the historic Reformed confessions of faith, the greatest Reformed theologians) have avoided these errors and have articulated a much sounder version of these doctrines.  (The sounder Calvinists have often referred to the less sound version of Calvinism as "Hyper-Calvinism.")  So as we look at each point of TULIP, I will lay out two broad interpretations--a basically sound interpretation and an unsound interpretation--and I will show briefly that the Catholic tradition agrees with the sound interpretation of each of the points (except for one substantial difference occurring in the very last point, the P, which I will discuss when we get there).

It should be noted that while I am going to defend the substance of the "sound interpretation" of these Calvinist doctrines, I should not be taken necessarily in all cases to be defending the language used to articulate that doctrinal substance.  The Catholic Church has been very wary over the centuries of people misspeaking when it comes to the doctrines of grace, due to the ease with which people tend to misunderstand these ideas and come to very harmful wrong conclusions regarding them.  Calvinist verbage (including the TULIP acrostic) is not always free from language that can be misleading, as even Calvinists themselves frequently acknowledge.

T - Total Depravity

Unsound interpretation:  The Fall of Adam destroyed the free will of man.  Since that time, men are unable to choose what is right but are determined to evil.  Their descent into evil has been so thorough that no one since the Fall has been able to think any good thought, feel anything right, or do anything good at all in any sense.  It might be asked how man can be blamed for sin if his free will has been destroyed.  The answer is that he is blamed in Adam.  Adam represented us when he ate the forbidden fruit, and so when he sinned, God regarded this sin as the sin of us all and blames us for it.  Therefore, we can be held responsible for our sins even though we can't avoid them.

Sound interpretation:  The Fall of Adam plunged the human race into sin, but it did not destroy our natural faculties as human beings.  We are still humans, made in the image of God, possessing reason and true free will (that is, the ability to make true choices, including moral choices).  However, while we retain our natural faculties, those faculties have become inclined to sin, so that fallen man, without grace, ever lives in rebellion against God and is thus doomed, apart from grace, to reap the fruit of sin in eternal damnation.  Fallen man still possesses the image of God, and this manifests itself in his ability to think true thoughts, have good natural affections, and make good choices to some extent, but never to the extent that he will emerge from his state of rebellion against God and be fundamentally reconciled to him apart from grace.

Most Calvinists hold to the latter, sound interpretation of Total Depravity.  For a couple of examples, take two classic Calvinist confessions of faith: the Canons of Dordt and the Westminster Confession.  The Canons of Dordt (Third and Fourth Head, Article 4) say that "there remain, however, in man since the fall, the glimmerings of natural light, whereby he retains some knowledge of God, or natural things, and of the difference between good and evil, and shows some regard for virtue and for good outward behavior."  They also say (Third and Fourth Head, Article 16) that "man by the fall did not cease to be a creature endowed with understanding and will, nor did sin which pervaded the whole race of mankind deprive him of the human nature, but brought upon him depravity and spiritual death."  The Westminster Confession (Chapter 9, section 1) says that "God hath endued the will of man with that natural liberty, that it is neither forced, nor by any absolute necessity of nature determined to good or evil."  Both of these statements go on to point out that, even though man is still man after the fall, and still possesses free will, he is bound in sin and is unable, without grace, to emerge from the state of sin and be reconciled to God.

This is the same position that is taught by the Catholic faith.  Here is Canon 22 of the Canons of the Council of Orange, which articulated the Catholic Church's official and authoritative response to the Semipelagian heresy back in the 6th century and remains authoritative today:

Concerning those things that belong to man. No man has anything of his own but untruth and sin. But if a man has any truth or righteousness, it is from that fountain for which we must thirst in this desert, so that we may be refreshed from it as by drops of water and not faint on the way.

Canon 5 says this:

If anyone says that not only the increase of faith but also its beginning and the very desire for faith, by which we believe in Him who justifies the ungodly and comes to the regeneration of holy baptism — if anyone says that this belongs to us by nature and not by a gift of grace, that is, by the inspiration of the Holy Spirit amending our will and turning it from unbelief to faith and from godlessness to godliness, it is proof that he is opposed to the teaching of the Apostles, for blessed Paul says, "And I am sure that he who began a good work in you will bring it to completion at the day of Jesus Christ" (Phil. 1:6). And again, "For by grace you have been saved through faith; and this is not your own doing, it is the gift of God" (Eph. 2:8). For those who state that the faith by which we believe in God is natural make all who are separated from the Church of Christ by definition in some measure believers.

The Council of Trent, which further articulated the Catholic Church's official teaching on grace, said this (Sixth Session, Chapter 1--page number removed):

The holy Synod declares first, that, for the correct and sound understanding of the doctrine of Justification, it is necessary that each one recognise and confess, that, whereas all men had lost their innocence in the prevarication of Adam-having become unclean, and, as the apostle says, by nature children of wrath, as (this Synod) has set forth in the decree on original sin,-they were so far the servants of sin, and under the power of the devil and of death, that not the Gentiles only by the force of nature, but not even the Jews by the very letter itself of the law of Moses, were able to be liberated, or to arise, therefrom; although free will, attenuated as it was in its powers, and bent down, was by no means extinguished in them.

While many Calvinists and the most enduring and central confessions of the Reformed churches have taught a sound interpretation of Total Depravity, there have been Calvinists (again, "Hyper-Calvinists" as their Calvinist adversaries call them) who have taught less sound interpretations.  One of the most memorable and dramatic examples (at least to me, having studied this example in my PhD thesis a number of years ago) is a certain strand of what is called "preparationist" theology among the English Puritans.  During the heyday of classic Puritanism in England and in colonial America, the doctrine of Total Depravity in some circles began to take on a sort of connotation which seemed to excuse sinners from obeying the gospel.  Puritan parishioners began to reason that if, without grace, no one is able to have faith and repentance, those who are without grace (all those who have not in fact been regenerated by grace) are unable to turn to God in faith and repentance and so cannot be expected to perform these acts.  Instead of performing these acts, then, they began to emphasize the need to focus on doing other acts they believed to be within the ability of fallen man--such as reading the Bible, coming to church, praying for repentance, trying to live as moral a life as possible.  Their idea was that if they did the things they could do, it might make it more likely that God would someday give them grace to do the things they couldn't do.  Eventually, among some, this got taken to the point that people stopped thinking they had any duty to obey the gospel but only to try to "prepare" themselves to receive grace.  Some Puritan pastors encouraged this way of thinking and preached to their people accordingly.  It was this extreme form of preparationist theology and preaching that inspired Jonathan Edwards, the great American Calvinist theologian and philosopher (who had a much sounder understanding of man's sinful state and man's free will in a sinful condition), to emphasize in his preaching man's remaining freedom even under sin and his consequent moral responsibility for his sinful acts and to write his great treatise on the freedom of the will (one of my favorite books--truly a masterpiece of theology and philosophy).  Edwards's followers eventually evolved into what become known as the "New England theology," which found itself frequently at odds with more conventional articulations of Calvinism because of its increasing tendency to emphasize in its language the remaining freedom of the will even under sin (raising the specter of "Arminianism" or even "Pelagianism" in many Calvinist minds, though unjustly in my opinion).  But this is a story for another time--albeit a fascinating one.

U - Unconditional Election

Unsound interpretation:  God, from all eternity, has ordained whatsoever comes to pass in history.  Therefore, everything is predestined, and there is nothing we can do about it.  What will be will be, and so it doesn't matter what we choose.  If I am destined to be saved, I will be saved, no matter what I do.  If I am destined to be damned, I will be damned, no matter what I do.  Nothing can ever be any way other than the way it is, according to God's eternal plan.  There is therefore no free will, for I can never do anything other than what God ordains me to do.  Those who are saved are forced to be saved, and those who are damned are forced to be damned.  God never gives either any chance to be anything else.  Evil is created by God in the same way that good is.  Both come from God and God acts equally in both.

Sound interpretation:  Everything that happens happens in accordance with God's eternal plan, but not in such a way as to imply a necessitating fatalism ("what will be will be, no matter what we do"), the destruction or subversion of free will, or the negation of the reality of contingent possibilities (different things may happen depending on other things that may happen or what we may do).  All good comes from God, but evil is not a positive entity that comes from God.  God does not create evil, but permits it to occur according to his plan because he uses it to accomplish perfectly the good that he wills.  Although evils which are contrary to God's nature occur in the world, yet they cannot ultimate subvert but, by God's perfect providence, ultimately help to secure the total fulfillment of God's good purposes.  God permitted the Fall of man to occur and all the evils that have flowed from it.  Among the mass of fallen humanity, God chooses to bring some to eternal salvation, while he chooses to permit others to reject him to the end and thus end up in eternal damnation.

All Calvinists that I have known or read have affirmed the latter interpretation rather than the former, though they are frequently accused by Catholics and others of affirming the former.  The Westminster Confession has these things to say about God's eternal decree and his providence in history (footnotes removed--as throughout this article):

God from all eternity did, by the most wise and holy counsel of His own will, freely, and unchangeably ordain whatsoever comes to pass: yet so, as thereby neither is God the author of sin, nor is violence offered to the will of the creatures, nor is the liberty or contingency of second causes taken away, but rather established. (3:1) 
Although, in relation to the foreknowledge and decree of God, the first Cause, all things come to pass immutably, and infallibly: yet, by the same providence, He ordereth them to fall out, according to the nature of second causes, either necessarily, freely, or contingently. (5:2)

God has chosen some men out of the mass of fallen humanity to bring to eternal salvation, and he has left others in their sinful condition and permitted them to perish.  Notice the Westminster Confession's care to avoid suggesting that God has produced evil in fallen sinners or has coerced or caused anyone to remain in sin or reject the gospel:

By the decree of God, for the manifestation of His glory, some men and angels are predestinated unto everlasting life, and others foreordained to everlasting death. (3:3) 
As God hath appointed the elect unto glory, so hath He, by the eternal and most free purpose of His will, foreordained all the means thereunto. Wherefore they who are elected, being fallen in Adam, are redeemed by Christ, are effectually called unto faith in Christ by His Spirit working in due season, are justified, adopted, sanctified, and kept by His power through faith unto salvation. Neither are any other redeemed by Christ, effectually called, justified, adopted, sanctified, and saved, but the elect only. (3:6) 
The rest of mankind God was pleased, according to the unsearchable counsel of His own will, whereby He extendeth or withholdeth mercy, as He pleaseth, for the glory of His sovereign power over His creatures, to pass by; and to ordain them to dishonour and wrath, for their sin, to the praise of His glorious justice. (3:7)

Regarding the idea that God works evil and damnation in the world in the same way he works good and salvation, see this concise article by Calvinist theologian R. C. Sproul.  In the article, Sproul has this to say:

The distortion of double predestination looks like this: There is a symmetry that exists between election and reprobation. God works in the same way and same manner with respect to the elect and to the reprobate. That is to say, from all eternity God decreed some to election and by divine initiative works faith in their hearts and brings them actively to salvation. By the same token, from all eternity God decrees some to sin and damnation (destinare ad peccatum) and actively intervenes to work sin in their lives, bringing them to damnation by divine initiative. In the case of the elect, regeneration is the monergistic work of God. In the case of the reprobate, sin and degeneration are the monergistic work of God. Stated another way, we can establish a parallelism of foreordination and predestination by means of a positive symmetry. We can call this a positive-positive view of predestination. This is, God positively and actively intervenes in the lives of the elect to bring them to salvation. In the same way God positively and actively intervenes in the life of the reprobate to bring him to sin. 
This distortion of positive-positive predestination clearly makes God the author of sin who punishes a person for doing what God monergistically and irresistibly coerces man to do. Such a view is indeed a monstrous assault on the integrity of God. This is not the Reformed view of predestination, but a gross and inexcusable caricature of the doctrine. Such a view may be identified with what is often loosely described as hyper-Calvinism and involves a radical form of supralapsarianism. Such a view of predestination has been virtually universally and monolithically rejected by Reformed thinkers. . . . 
In the Reformed view God from all eternity decrees some to election and positively intervenes in their lives to work regeneration and faith by a monergistic work of grace. To the non-elect God withholds this monergistic work of grace, passing them by and leaving them to themselves. He does not monergistically work sin or unbelief in their lives.

Or listen to the great Calvinist theologian Jonathan Edwards:

They who object, that this doctrine makes God the Author of Sin, ought distinctly to explain what they mean by that phrase, The Author of Sin. I know the phrase, as it is commonly used, signifies something very ill. If by the Author of Sin, be meant the Sinner, the Agent, or Actor of Sin, or the Doer of a wicked thing; so it would be a reproach and blasphemy, to suppose God to be the Author of Sin. In this sense, I utterly deny God to be the Author of Sin; rejecting such an imputation on the Most High, as what is infinitely to be abhorred; and deny any such thing to be the consequence of what I have laid down. But if, by the Author of Sin, is meant the permitter, or not a hinderer of Sin; and, at the same lime, a disposer of the state of events, in such a manner, for wise, holy, and most excellent ends and purposes, that Sin, if it be permitted or not hindered, will most certainly and infallibly follow: I say, if this be all that is meant, by being the Author of Sin, I do not deny that God is the Author of Sin, (though I dislike and reject the phrase, as that which by use and custom is apt to carry another sense,) it is no reproach for the Most High to be thus the Author of Sin. This is not to be the Actor of Sin, but, on the contrary, of holiness. . . . 
[T]here is a great difference between God being; concerned thus, by his permission, in an event and act, which, in the inherent subject and agent of it, is sin, (though the event will certainly follow on his permission,) and his being concerned in it by producing it and exerting the act of sin; or between his being the orderer of its certain existence, by not hindering it, under certain circumstances, and his being the proper actor or author of it, by a positive agency or efficiency. And this, notwithstanding what Dr. Whitby offers about a saying of philosophers, that causa defitiens, in rebus necessariis, ad causam per se efficientem reducenda est. As there is a vast difference between the sun being the cause of the lightsomeness and warmth of the atmosphere, and the brightness of gold and diamonds, by its presence and positive influence; and its being the occasion of darkness and frost, in the night, by its motion, whereby it descends below the horizon. The motion of the sun is the occasion of the latter kind of events; but it is not the proper cause, efficient, or producer of them; though they are necessarily consequent on that motion, under such circumstances: no more is any action of the Divine Being the cause of the evil of men’s Wills. If the sun were the proper cause of cold and darkness, it would be the fountain of these things, as it is the fountain of light and heat: and then something might be argued from the nature of cold and darkness, to a likeness of nature in the sun; and it might be justly inferred, that the sun itself is dark and cold, and that his beams are black and frosty. But from its being the cause no otherwise than by its departure, no such thing can be inferred, but the contrary; it may justly be argued, that the sun is a bright and hot body, if cold and darkness are found to be the consequence of its withdrawment; and the more constantly and necessarily these effects are connected with and confined to its absence, the more strongly does it argue the sun to be the fountain of light and neat. So, inasmuch as sin is not the fruit of any positive agency or influence of the Most High, but, on the contrary, arises from the withholding of his action and energy, and, under certain circumstances, necessarily follows on the want of his influence; this is no argument that he is sinful, or his operation evil, or has any thing of the nature of evil; but, on the contrary, that he, and his agency, are altogether good and holy, and that he is the fountain of all holiness. It would be strange arguing, indeed, because men never commit sin, but only when God leaves them to themselves, and necessarily sin when he dues so, that therefore their sin is not from themselves, but from God; and so, that God must be a sinful being: as strange as it would be to argue, because it is always dark when the sun is gone, and never dark when the sun is present, that therefore all darkness is from the sun, and that his disk and beams must needs be black. (Freedom of the Will, Part IV. Section IX)

All of this is the same as what is taught by Catholic doctrine.  Catholic doctrine teaches that God's eternal plan includes all that comes to pass and that it cannot be thwarted:

The Holy Scriptures repeatedly confess the universal power of God. He is called the "Mighty One of Jacob", the "LORD of hosts", the "strong and mighty" one. If God is almighty "in heaven and on earth", it is because he made them. Nothing is impossible with God, who disposes his works according to his will. He is the Lord of the universe, whose order he established and which remains wholly subject to him and at his disposal. He is master of history, governing hearts and events in keeping with his will: "It is always in your power to show great strength, and who can withstand the strength of your arm?  (Catechism of the Catholic Church, #268-269--footnotes removed) 
The witness of Scripture is unanimous that the solicitude of divine providence is concrete and immediate; God cares for all, from the least things to the great events of the world and its history. The sacred books powerfully affirm God's absolute sovereignty over the course of events: "Our God is in the heavens; he does whatever he pleases." And so it is with Christ, "who opens and no one shall shut, who shuts and no one opens". As the book of Proverbs states: "Many are the plans in the mind of a man, but it is the purpose of the LORD that will be established."  (Catechism #303--footnotes removed) 
The truth that God is at work in all the actions of his creatures is inseparable from faith in God the Creator. God is the first cause who operates in and through secondary causes: "For God is at work in you, both to will and to work for his good pleasure."  (Catechism #308) 
St. Thomas More, shortly before his martyrdom, consoled his daughter: "Nothing can come but that that God wills. And I make me very sure that whatsoever that be, seem it never so bad in sight, it shall indeed be the best." (Catechism #313--footnotes removed)

The Catholic Encyclopedia article on "Predestination" puts it this way:

 According to the doctrinal decisions of general and particular synods, God infallibly foresees and immutably preordains from eternity all future events (cf. Denzinger, n. 1784), all fatalistic necessity, however, being barred and human liberty remaining intact (Denz., n. 607).

Regarding moral evil:

God is in no way, directly or indirectly, the cause of moral evil. He permits it, however, because he respects the freedom of his creatures and, mysteriously, knows how to derive good from it: . . . 
For almighty God. . ., because he is supremely good, would never allow any evil whatsoever to exist in his works if he were not so all-powerful and good as to cause good to emerge from evil itself. . . . (Catechism #311--footnotes removed)

The Catechism of St. Pius X talks about God's permission of moral evil in this way (in the section on "The First Article of the Creed"):

10 Q. Does God take any interest in the world and in the things created by Him?
A. Yes, God takes an interest in the world and in all things created by Him; He preserves them, and governs them by His infinite goodness and wisdom; and nothing happens here below that He does not either will or permit. 
11 Q. Why do you say that nothing happens here below that He does not either will or permit?
A. We say that nothing happens here below that He does not either will or permit, because there are some things which God wills and commands, while there are others which He simply does not prevent, such as sin. 
12 Q. Why does not God prevent sin?
A. God does not prevent sin, because even from the very abuse man makes of the liberty with which He is endowed, God knows how to bring forth good and to make His mercy or His justice become more and more resplendent. 

If God ordains all that comes to pass, and if all good comes from him and all evil is permitted willingly by him, and if all saving moral goodness that we humans can possess is a gift of grace through Christ (as we saw earlier and will see more later), and if some end up saved and others end up damned, it follows that those who are saved are saved by the election and mercy of God and as a gift of his grace, and that those who are damned are permitted to be damned by God, who decided not to give them the same gift of salvation he gave to his elect.  Accordingly, this is what is affirmed by Catholic doctrine.  Ludwig Ott, in his well-respected and widely-used book on Catholic doctrine, Fundamentals of Catholic Dogma (Rockford, IL: TAN Books, 1974 {orig. 1952}, 242-245), explains (capitalization removed) that it is Catholic dogma that "God, by his eternal resolve of will, has predetermined certain men to eternal blessedness."  Ott goes on:

This doctrine is proposed by the Ordinary and General Teaching of the Church as a truth of Revelation. The doctrinal definitions of the Council of Trent presuppose it . . . The reality of Predestination is clearly attested to in Rom 8:29 et seq: . . . cf. Mt 25:34, Jn 10:27 et seq., Acts 13:48, Eph 1:4 et seq. . . . Predestination is a part of the Eternal Divine Plan of Providence. (found here--ellipsis in original)

Fr.  Reginald Garrigou-Lagrange, in his book Predestination [(Charlotte, NC: TAN Books, 2013), p. 10], which is pretty universally regarded as a modern classic reference on Catholic theology regarding predestination, makes the same point:

But in any case, from this minimum admitted by all we get three propositions to which all Catholic theologians subscribe. They are: (1) Predestination to the first grace is not because God foresaw our naturally good works, nor is the beginning of salutary acts due to natural causes; (2) predestination to glory is not because God foresaw we would continue in the performance of supernaturally meritorious acts apart from the special gift of final perseverance; (3) complete predestination, in so far as it comprises the whole series of graces from the first up to glorification, is gratuitous or previous to foreseen merits. These three propositions are admitted by all Catholic theologians.

St. Thomas Aquinas, one of the greatest Doctors of the Catholic Church, talks about how some have been predestined by God to grace and to eternal life, while others have been "reprobated" by God--that is, passed over by God and permitted by his providence to remain in sin:

God does reprobate some. For it was said above (Article 1) that predestination is a part of providence. To providence, however, it belongs to permit certain defects in those things which are subject to providence, as was said above (I:22:2). Thus, as men are ordained to eternal life through the providence of God, it likewise is part of that providence to permit some to fall away from that end; this is called reprobation. Thus, as predestination is a part of providence, in regard to those ordained to eternal salvation, so reprobation is a part of providence in regard to those who turn aside from that end. Hence reprobation implies not only foreknowledge, but also something more, as does providence, as was said above (I:22:1). Therefore, as predestination includes the will to confer grace and glory; so also reprobation includes the will to permit a person to fall into sin, and to impose the punishment of damnation on account of that sin.  (Summa Theologica, First Part, Question 23, Article 3--from the New Advent website, embedded links removed)

In the early medieval Church, the doctrine of predestination was dealt with in a number of councils which (as the Catholic Encyclopedia article above alluded to) have informed the development of Catholic thinking on this subject.  Two of these councils were the Council of Quiercy (853) and the Council of Valence (855).  Here is a selection from the canons of Quiercy [Guido Stucco, God's Eternal Gift: A History of the Catholic Doctrine of Predestination from Augustine to the Renaissance (Xlibris, 2009), 350-351--footnotes removed]:

     Almighty God created man without sin, righteous and endowed with free will.  He placed man in paradise, and wanted him to dwell in the sanctity of justice.  Man, by making bad use of his free will, sinned and fell (from this state of justice), becoming the 'mass of perdition' of the entire humankind.  However, the good and righteous God, according to his foreknowledge (secundum praescientiam suam), chose out of this mass of perdition those whom he predestined through grace (Rom 8:29 ff; Eph 1:11) to eternal life, and likewise, he predestined eternal life for them.  He foreknew that everybody else, whom he abandoned in the mass of perdition according to his just decree, was going to perish, though he did not predestine them to perish; rather, being just, he predestined eternal punishment for them.  Because of this, we speak of only one divine predestination, which pertains to either the gift of grace or to the retribution of justice. . . . 
     We lost the freedom of will in the first man, but got it back through Christ our Lord.  We have free will to do what is good, which is preceded and helped by God's grace; we have free will to do what is evil, as it is abandoned by God's grace.  We [can say] we have free will because it is freed and healed from corruption by grace. . . . 
     Almighty God wants "all men to be saved" (1 Tim 2:4) without exception (sine exceptione), even though not all will be saved.  The fact that some are saved, is the gift of the saving God; the fact that some perish, is their own fault.

Here is part of Canon 3 from the Council of Valence (Stucco, 363-364):

     In regard to God's predestination, we wished in the past and still faithfully wish to claim in the present, on the basis of the apostolic authority, that: "Does not the potter have a right over the clay to make out of the same lump one vessel for a noble purpose and another for an ignoble one?" (Rom 9:21), and also according to what immediately comes next: "What if God, wishing to show his wrath and make known his power, has endured with much patience the vessels of wrath made for destruction?  This was to make known the riches of his glory to the vessels of mercy, which he has prepared previously for glory" (Rom 9:22).  With confidence, we profess the predestination of the elect to life and the predestination of the impious to death: in the election of those who are to be saved, the mercy of God anticipates their good merit; in the damnation of those who will perish, their guilt anticipates just judgment.  "By means of predestination, God has only established what he is going to do either out of gratuitous mercy, or out of just judgment," as we read in the Scriptures:  "He has done what will be," (Is 45:11 LXX).  In the case of evil people, he has foreknown their malice, which originates from themselves, but has not predestined it, because it does not stem from him . . . [as the] Second Council of Orange said: "That some people have been predestined by the divine power," meaning that they could not be otherwise, "not only we do not believe, but if there are some who wish to believe something so evil, we anathemize and detest them."

"The fact that some are saved, is the gift of the saving God; the fact that some perish, is their own fault."  This same statement, with nearly the same wording, was articulated by the Reformed Confession of 1536:  "Our salvation is from God, but from ourselves there is nothing but sin and damnation. (Art. 9)" (found here).

In the year 785, Pope Hadrian I articulated briefly and succinctly the Catholic teaching on predestination in a letter to the bishops of Spain, where there was apparently some confusion on the topic.  Some were asking what the point of doing anything is if everything is predestined, and others were asking what the point of asking God for help is if we can make our own choices.

    As for that, however, which some of these say, that predestination to life or to death is in the power of God and not in ours; they say: "Why do we try to live, because it is in the power of God?"; again others say: "Why do we ask God, that we may not be overcome by temptation, since it is in our power, as in the freedom of will?"  For truly they are able to render or to accept no plan, being ignorant . . . [of the words] of blessed Fulgentius [against a certain Pelagius]:  "Therefore, God in the eternity of His changelessness has prepared works of mercy and justice . . . but for men who are to be justified He has prepared merits; He has prepared rewards for those who are to be glorified; but for the wicked He has not prepared evil wills or evil works, but He has prepared for them just and eternal punishments.  This is the eternal predestination of the future works of God, which as we have always acknowledged to be taught to us by apostolic doctrine, so also faithfully we proclaim. . . ."  (Henry Denzinger, The Sources of Catholic Dogma, tr. Roy J. Deferrari [Fitzwilliam, NH: Loreto Publications, 2002], a translation of "the thirtieth edition of Enchiridion Symbolorum by Henry Denzinger, revised by Karl Rahner, S.J., published in 1954, by Herder & Co., Freiburg", p. 120, #300--ellipses and brackets in original)

In short, God is the source of the good works of the saints as well as of their eternal reward, but he is not the positive source of the evil works of the damned, though he ordains their eternal punishment.

L - Limited Atonement

Unsound interpretation:  Christ died only for the elect.  Therefore, his atonement does not have sufficient merit or power to save the non-elect (the reprobate).  Even if the reprobate should come to Christ, they would have to be rejected, because no atonement was made for them.  Salvation is offered only to the elect, the others not being invited.

Sound interpretation:  Christ died only for the elect, in the sense that in God's eternal plan the atonement was only intended to actually fully accomplish the eternal salvation of the elect and in fact it only accomplishes their eternal salvation.  However, the atonement, being of infinite value, is sufficient to save all men, elect and reprobate, and it is sincerely offered to all men, so that any who come to Christ have plentiful grace available to them to accomplish fully their eternal salvation.

Most Calvinists I have known and read have embraced the latter rather than the former interpretation.  Well-respected Calvinist theologian Loraine Boettner, in his book The Reformed Doctrine of Predestination (Eerdmans, 1932 - footnote references added to text), explains:

This doctrine does not mean that any limit can be set to the value or power of the atonement which Christ made. The value of the atonement depends upon, and is measured by, the dignity of the person making it; and since Christ suffered as a Divine-human person the value of His suffering was infinite. . . .
While the value of the atonement was sufficient to save all mankind, it was efficient to save only the elect. It is indifferently well adapted to the salvation of one man to that of another, thus making the salvation of every man objectively possible; yet because of subjective difficulties, arising on account of the sinners own inability either to see or appreciate the things of God, only those are saved who are regenerated and sanctified by the Holy Spirit. The reason why God does not apply this grace to all men has not been fully revealed.  (Chapter XII, 2, 3) 
Will any one contend that God cannot sincerely offer salvation to a free moral agent unless in addition to the invitation He exerts a special influence which will induce the person to accept it? After a civil war in a country it often happens that the victorious general offers free pardon to all those In the opposing army, provided they will lay down their arms, go home, and live peaceable lives, although he knows that through pride or malice many will refuse. He makes the offer in good faith even though for wise reasons he determines not to constrain their assent, supposing him possessed of such power. . . .
When the Gospel is presented to mankind in general nothing but a sinful unwillingness on the part of some prevents their accepting and enjoying it. No stumbling block is put in their way. All that the call contains is true; it is adapted to the conditions of all men and freely offered if they will repent and believe. No outside influence constrains them to reject it. The elect accept; the non-elect may accept if they will, and nothing but their own nature determines them to do otherwise. "According to the Calvinistic scheme," says Dr. Hodge, "the non-elect have all the advantages and opportunities of securing their salvation, that, according to any other scheme, are granted to mankind indiscriminately. Calvinism teaches that a plan of salvation adapted to all men and adequate for the salvation of all, is freely offered to the acceptance of all, although in the secret purpose of God He intended that it should have precisely the effect which in experience it is found to have. He designed in its adoption to save His own people, but consistently offers its benefits to all who are willing to receive them. More than this no anti-Calvinist can demand." [137--Systematic Theology, II., p. 644.]  (Chapter XXI, 2)

In other words, in the Calvinist scheme, the atonement is infinite in value and sufficient for the sins of all men.  It is freely offered to all men.  It makes the salvation of all men objectively possible, removing all barriers to their salvation apart from their own unwillingness to receive it.  It gives to all men the ability to be saved if they will choose to avail themselves of the opportunity.  But only the elect will do so, because only to the elect does God give the gift of a good will.  The reprobate are not caused, not coerced, but permitted to reject the real opportunity they have been given and so fail to attain eternal salvation.

The Catholic view is no different, although the Church has taught Catholics to be averse to the language of "limited atonement" because of its natural false connotations (as expressed in the "unsound interpretation" above).  So Catholics ought to avoid some of the Calvinist terminology here.  Calvinists themselves sometimes complain of the connotations of their own terminology, thus agreeing to some extent with the Catholic Church's concern on this point.  Loraine Boettner, for example, in the same book quoted from just above, complains a little about the term "limited atonement":

The meaning might be brought out more clearly if we used the phrase "Limited Redemption" rather than "Limited Atonement." The Atonement is, of course, strictly an infinite transaction; the limitation comes in, theologically, in the application of the benefits of the atonement, that is in redemption. But since the phrase "Limited Atonement" has become well established in theological usage and its meaning is well known we shall continue to use it. (Chapter XII, 1)

But, apart from questions of terminology and connotations, in my experience what most Calvinists mean by "limited atonement" is consistent with Catholic doctrine on this point.  We saw above that God has elected some to eternal salvation and passed by others in his eternal plan.  Since he ordains freely all that comes to pass and is not forced or locked into doing anything by anything coming ultimately from outside himself, since he is the First Cause, we must say that he chooses those he will save in a free and unconstrained way.  The plan of history flows from him rather than being something forced upon him or something he discovers as involving factors originating ultimately from outside himself, outside his free acts of causing and permitting.  Therefore, we must say that if some men are not ultimately saved, it was not God's eternal intention to bring about their salvation.  Therefore, Christ's atonement was not intended by God to bring about their eternal salvation, and it does not in fact bring about their eternal salvation.  In the words of the Council of Trent (Sixth Session, Chapter III--page number removed), "though He died for all, yet do not all receive the benefit of His death, but those only unto whom the merit of His passion is communicated."  This is all that Calvinists typically mean by "limited atonement."  Christ died for all men, in that his atonement is sufficient to save all men, in that it provides sufficient opportunity and grace to enable all men to be saved if they will choose to avail themselves of their opportunity, and in that God intended it to provide such objective opportunity to all men and to make possible the free and sincere offer of the gospel to all men; though, in his eternal plan, he predestined that the atonement would only actually end up bringing about the eternal salvation of the elect through the application of divine grace.  All this both Catholics and the sounder Calvinists grant, so there is no substantial difference in doctrine upon this point (except in relation to the doctrine of the perseverance of the saints--the P in TULIP--which we will discuss further below).

I - Irresistible Grace

Unsound interpretation:  When God converts a sinner, he sends him a grace he cannot resist no matter how hard he tries.  Thus, man is not converted through any act of his own will but only by God's act of dragging him apart from his will into reconciliation with God.  Only God acts in conversion; we do not act.

Sound interpretation:  When God converts a sinner, he sends him a grace that efficaciously opens his eyes to see the truth and beauty of the gospel so that he chooses willingly to come to Christ.  The sinner could reject this grace if he wished to do so, but he does not want to because he is effectively persuaded by it to desire freely to turn to God in faith and repentance.

Some Calvinists seem to have understood the efficaciousness of grace in the unsound manner described above, but from my experience and reading I would say that the most sophisticated and classic expressions of Calvinistic doctrine have understood it in the latter, sounder sense.  The Westminster Confession, for example, is quite clear on this point:

All those whom God hath predestinated unto life, and those only, He is pleased in His appointed and accepted time effectually to call, by His Word and Spirit, out of that state of sin and death, in which they are by nature, to grace and salvation by Jesus Christ; enlightening their minds spiritually and savingly to understand the things of God; taking away their heart of stone, and giving unto them a heart of flesh; renewing their wills, and by His almighty power determining them to that which is good, and effectually drawing them to Jesus Christ: yet so, as they come most freely, being made willing by His grace. (10:1--emphasis added)

Once again, Calvinist author Loraine Boettner provides helpful clarification:

On other grounds also it may be shown that certainty is consistent with free agency. We are often absolutely certain how we will act under given conditions so far as we are free to act at all. A parent may be certain that he will rescue a child in distress, and that in doing so he will act freely. God is a free agent, yet it is certain that He will always do right. The holy angels and redeemed saints are free agents, yet it is certain that they will never sin; other- wise there would be no assurance of their remaining in heaven. On the other hand, it is certain that the Devil, the demons and fallen men will commit sin, although they are free agents. A father often knows how his son will act under given circumstances and by controlling these he determines beforehand the course of action which the son follows, yet the son acts freely. If he plans that the son shall be doctor, he gives him encouragement along that line, persuades him to read certain books, to attend certain schools, and so presents the outside inducements that his plan works out. In the same manner and to an infinitely greater extent God controls our actions so that they are certain although we act freely. His decree does not produce the event, but only renders its occurrence certain; and the same decree which determines the certainty of the action at the same time determines the freedom of the agent in the act.  (The Reformed Doctrine of Predestination, Chapter XVI, 2) 
In accordance with this we believe that, without destroying or impairing the free agency of men, God can exercise over them a particular providence and work in them through His Holy Spirit so that they will come to Christ and persevere in His service. We believe further that none have this will and desire except those whom God has previously made willing and desirous; and that He gives this will and desire to none but His own elect. But while thus induced, the elect remain as free as the man that you persuade to take a walk or to invest in government securities.  (Chapter XVI, 5)

In other words, God efficaciously draws the elect to Christ.  Because he does so, they will certainly come.  But they also come completely freely.  Grace does not subvert or destroy their will or intellect but rather works by persuading them effectively to do the right thing.

OK, but can they do otherwise?  The Council of Trent (Sixth Session, Chapter V) says that the sinner who is the subject of the inspiration of divine grace is not "utterly without doing anything while he receives that inspiration, forasmuch as he is also able to reject it."  The Catholic view holds that when God converts us, we are not converted as blocks or stones but as human beings with free will, and so our will must cooperate with grace (even if that cooperation is itself a product and gift of grace).  If grace is irresistible, it would seem that the will cannot do otherwise than accept it.  And if the will cannot do otherwise, then how is it truly free in its acceptance?  Boettner comments:

Nor does it follow from the absolute certainty of a person's acts that he could not have acted otherwise. He could have acted otherwise if he had chosen to have done so. Oftentimes a man has power and opportunity to do that which it is absolutely certain he will not do, and to refrain from doing that which it is absolutely certain he will do. That is, no external influence determines his actions. Our acts are in accordance with the decrees, but not necessarily so we can do otherwise and often should. Judas and his accomplices were left to fulfill their purpose, and they did as their wicked inclinations prompted them. Hence Peter charged them with the crime, but he at the same time declared that they had acted according to the purpose of God,--"Him being: delivered up by the determinate counsel and foreknowledge of God, ye by the hands of lawless men did crucify and slay," Acts 2:23. (Chapter XVI, 2)

In other words, those who receive efficacious grace can do otherwise than accept it, but it is certain they will not.

Calvinist theologian Jonathan Edwards, in Freedom of the Will (Part I, Section IV), also comments on the fact that both in reference to the person who rejects the gospel and the person who accepts it, it may be certain that they will do what they do, but at the same time they could have done otherwise.  Edwards articulates this using the language of "moral inability" vs. "natural inability":

We are said to be naturally unable to do a thing, when we cannot do it if we will, because what is most commonly called nature does not allow of it, or because of some impeding defect or obstacle that is extrinsic to the Will; either in the Faculty of understanding, constitution of body, or external objects. Moral Inability consists not in any of these things; but either in the want of inclination; or the strength of a contrary inclination; or the want of sufficient motives in view, to induce and excite the act of the Will, or the strength of apparent motives to the contrary. Or both these may be resolved into one; and it may be said in one word, that moral Inability consists in the opposition or want of inclination. For when a person is unable to will or choose such a thing, through a defect of motives, or prevalence of contrary motives, it is the same thing as his being unable through the want of an inclination, or the prevalence of a contrary inclination, in such circumstances, and under the influence of such views. . . . 
But it must be observed concerning moral Inability, in each kind of it, that the word Inability is used in a sense very diverse from its original import. The word signifies only a natural Inability, in the proper use of it; and is applied to such cases only wherein a present will or inclination to the thing, with respect to which a person is said to be unable, is supposable. It cannot be truly said, according to the ordinary use of language, that a malicious man, let him be never so malicious, cannot hold his hand from striking, or that he is not able to show his neighbor kindness; or that a drunkard, let his appetite be never so strong, cannot keep the cup from his mouth. In the strictest propriety of speech, a man has a thing in his power, if he has it in his choice, or at his election: and a man cannot be truly said to be unable to do a thing, when he can do it if he will. It is improperly said, that a person cannot perform those external actions, which are dependent on the act of the Will, and which would be easily performed, if the act of the Will were present. And if it be improperly said, that he cannot perform those external voluntary actions, which depend on the Will, it is in some respect more improperly said, that he is unable to exert the acts of the Will themselves; because it is more evidently false, with respect to these, that he cannot if he will: for to say so, is a downright contradiction; it is to say, he cannot will, if he does will. And in this case, not only is it true, that it is easy for a man to do the thing if he will, but the very willing is the doing; when once he has willed, the thing is performed; and nothing else remains to be done. Therefore, in these things, to ascribe a non-performance to the want of power or ability, is not just; because the thing wanting, is not a being able, but a being willing. There are faculties of mind, and a capacity of nature, and every thing else, sufficient, but a disposition: nothing is wanting but a will.

Calvinists are forever clarifying the misconception of their doctrine that would suggest they are teaching that man is dragged by grace against his will to come to Christ.  They often acknowledge that the Calvinist terminology itself here can be misleading.  Boettner once again:

The special grace which we refer to as efficacious is sometimes called irresistible grace. This latter term, however, is somewhat misleading since it does suggest that a certain overwhelming power is exerted upon the person, in consequence of which he is compelled to act contrary to his desires, whereas the meaning intended, as we have stated before, is that the elect are so influenced by divine power that their coming is an act of voluntary choice.  (The Reformed Doctrine of Predestination, Chapter XIII, 7)

Catholic doctrine agrees with the sounder Calvinists on the point of the efficaciousness of divine grace.  Let me quote again from Canon 5 of the Canons of the Second Council of Orange:

If anyone says that not only the increase of faith but also its beginning and the very desire for faith, by which we believe in Him who justifies the ungodly and comes to the regeneration of holy baptism — if anyone says that this belongs to us by nature and not by a gift of grace, that is, by the inspiration of the Holy Spirit amending our will and turning it from unbelief to faith and from godlessness to godliness, it is proof that he is opposed to the teaching of the Apostles, for blessed Paul says, "And I am sure that he who began a good work in you will bring it to completion at the day of Jesus Christ" (Phil. 1:6). And again, "For by grace you have been saved through faith; and this is not your own doing, it is the gift of God" (Eph. 2:8).

Catholic doctrine is crystal clear that all good that we have relative to salvation is a gift of God coming from his grace through the sacrifice and merits of Christ.  It is not only the completion of good actions that comes from God, but also the very beginning of our good actions all the way down to the basic good will itself.  If we have a good will, it is entirely a gift of God's grace.  (Just read through the entirety of the Canons of Orange and ask yourself how this point could be emphasized any more clearly or strongly!)  As the Catechism of the Catholic Church puts it (#2001--footnotes removed):

The preparation of man for the reception of grace is already a work of grace. This latter is needed to arouse and sustain our collaboration in justification through faith, and in sanctification through charity. God brings to completion in us what he has begun, "since he who completes his work by cooperating with our will began by working so that we might will it:"

Then follows a quotation from St. Augustine:

Indeed we also work, but we are only collaborating with God who works, for his mercy has gone before us. It has gone before us so that we may be healed, and follows us so that once healed, we may be given life; it goes before us so that we may be called, and follows us so that we may be glorified; it goes before us so that we may live devoutly, and follows us so that we may always live with God: for without him we can do nothing.

Calvinsts sometimes complain about Catholic language talking about how man's will "cooperates" with grace, as if this suggests that man's will contributes something to salvation in addition to what God's grace contributes.  But, obviously, this is not what Catholic teaching intends.  Yes, the will of the Christian must cooperate with divine grace.  This is only to say that grace does not destroy or subvert human will but rather perfects it by bringing it to function properly.  The sounder Calvinist doctrine affirms the same.  But it is imperative that it not be forgotten that man's cooperation with divine grace is itself a fruit of divine grace.  There is no idea here of any independent contribution from man.  The idea that man makes an independent contribution to salvation is precisely the idea of the Semipelagianism that the Catholic Church has condemned so thoroughly time and time again.  No, as the Catechism of the Catholic Church (#2011) says, "[t]he saints have always had a lively awareness that their merits were pure grace."  And because even our good will is in its entirety a gift of divine grace, grace must be efficacious.  If God gives a person the gift of a good will, that person will have a good will.  God's grace does not need to be met with some independent contribution from the will, without which grace remains ineffective.  Grace itself provides the very assent of the will that cooperates with it.

Fr. John Hardon, in his Course on Grace: Part IIA - Grace Considered Intensively, Chapter XV, comments on Catholic dogma regarding efficacious grace:

It is a dogma of the Catholic faith that there exists a truly sufficient but inefficacious grace, and also that there exists a truly efficacious grace which, however, is not necessitating. 
A truly sufficient grace is sufficient for placing a salutary act. It carries with it the power of producing such an act. . . .
By a truly efficacious grace is meant one that will be (is) infallibly followed by the act to which it tends, e.g. contrition. If you receive such a grace, even before your will consents to it, that grace is infallibly “sure of success;” it will infallibly procure your consent, produce that act – of contrition. But although it infallibly procures your consent, it does not necessitate you to consent: it leaves you free to dissent. Your will will infallibly say "yes" to it, but it is free to say "no.”

God gives sufficient grace to all, so that there is no obstacle to a person coming to Christ outside his own free refusal to avail himself of the opportunity presented to him by the offer of salvation through Christ.  God commands us to return to him in reliance on his grace.  In order for us to be able to fulfill this command, God must make divine grace available to us upon condition that we will choose to make good use of it.  This is why Catholic doctrine insists that God has provided "sufficient grace" to all men.  All obstacles external to the will have been removed.  However, no one will choose to avail himself of the opportunity to return to God unless God gives him the gift not only of the ability to come to Christ if he will, but also the willingness itself, and it is efficacious grace which provides this willingness to those whom God has chosen.  The sounder Calvinists and orthodox Catholics are fundamentally one on all of these points.

P - The Perseverance of the Saints

Unsound interpretation:  God guarantees that anyone who has once been regenerated will definitely attain eternal salvation.  Therefore, we don't have to do anything to strive for it, or to watch and be wary lest we fall, since we can't fall.  We should never do anything out of concern to maintain our right relationship with God, but should leave it entirely in God's hands and so not take personal care for it.  Instead, we should just live spontaneously, knowing that if God has ordained some good work for us to do, he will cause us to do it.

Sounder interpretation:  God has promised that all those whom he regenerates and brings to faith and repentance he will prevent from ever finally falling away and so bring them safe at last to eternal salvation.  So we can rest assured of our eternal salvation and trust in God's grace.  However, this doesn't mean that we are not still required to be diligent and strive to persevere and grow in holiness, for it is precisely by means of our striving, to which we are moved by God's grace, that God will in the end bring us to eternal salvation.

I have heard people maintain the "unsound" interpretation or something like it on this point, but I don't recall ever hearing it from any serious Calvinist or Calvinist theologian.  The classic Calvinist doctrine on this point is expressed in the "sounder interpretation."

Here is the Westminster Confession on the doctrine of perseverance (Chapter 17--footnotes removed):

1. They, whom God hath accepted in His Beloved, effectually called, and sanctified by His Spirit, can neither totally, nor finally, fall away from the state of grace: but shall certainly persevere therein to the end, and be eternally saved.
2. This perseverance of the saints depends not upon their own free will, but upon the immutability of the decree of election flowing from the free and unchangeable love of God the Father; upon the efficacy of the merit and intercession of Jesus Christ; the abiding of the Spirit, and of the seed of God within them; and the nature of the covenant of grace: from all which ariseth also the certainty and infallibility thereof.
3. Nevertheless, they may, through the temptations of Satan and of the world, the prevalency of corruption remaining in them, and the neglect of the means of their preservation, fall into grievous sins; and, for a time, continue therein: whereby they incur God’s displeasure, and grieve His Holy Spirit, come to be deprived of some measure of their graces and comforts, have their hearts hardened,m and their consciences wounded, hurt and scandalize others, and bring temporal judgments upon themselves.

You probably noted that while on all the other points I contrasted an "unsound" interpretation with a "sound" interpretation, on this point I contrast an "unsound" with a "sounder" interpretation.  This is because on this point, unlike with the other four, even the best Calvinist interpretation deviates from sound Catholic doctrine to some degree.  I think we can distinguish three parts to the Calvinist doctrine of the perseverance of the saints:  1. All those whom God has elected to eternal salvation will certainly persevere to the end and attain eternal salvation.  2. There is a fundamental difference between the elect and the reprobate.  Considering each in terms of the whole course of their existence (as opposed to one isolated moment in their lives), the elect receive a victory over sin that the reprobate never receive.  Whatever repentance and holiness the reprobate attain by God's grace in this life, they are eventually conquered by sin and die in a state of enmity with God, in which they are confirmed forever.  So only the elect are ever the children of God in the fullest sense.  The reprobate may receive some temporary benefits from God's grace, but they are never possessers of the full, eternal aspects of justification, sanctification, or adoption.  3. All those who are brought to faith and repentance in any real sense at any one moment in their lives will certainly be given the gift of final perseverance by God and so will attain to eternal salvation.  In other words, only the elect ever actually come to any real faith and repentance.  The best the reprobate ever attain to is a kind of partial repentance which leaves them in the depths of their heart in a continuing state of rejection of God.

Catholic doctrine agrees with the first two of these three points but rejects the third.  The Catholic Church does not teach that all who are in any real sense regenerated or brought to faith and repentance at any moment in their lives are certainly elect and will be given the gift of final perseverance.  Catholic doctrine allows for the idea that God may give a temporary regeneration, a temporary faith and repentance, to some of the reprobate but withhold from them the gift of final perseverance, granting them a temporary taste of the life of Christ in this world but not the fullness of eternal life in Christ.

This also creates a real difference between Calvinist and Catholic doctrines regarding the possibility of being assured that one is elect and will attain eternal salvation.  Calvinists, logically, link their doctrine of assurance to their doctrine of perseverance.  Since all the regenerate are elect, if one looks within oneself and perceives signs that one has real faith and repentance, one can know that one is among the elect and will persevere to the end.  Catholic theology, on the other hand, does not allow for this unbreakable connection.

Here is the Council of Trent (Sixth Session, Chapters XII and XIII--page numbers removed) on these matters:

No one, moreover, so long as he is in this mortal life, ought so far to presume as regards the secret mystery of divine predestination, as to determine for certain that he is assuredly in the number of the predestinate; as if it were true, that he that is justified, either cannot sin any more, or, if he do sin, that he ought to promise himself an assured repentance; for except by special revelation, it cannot be known whom God hath chosen unto Himself. . . .
So also as regards the gift of perseverance, of which it is written, He that shall persevere to the end, he shall be saved:-which gift cannot be derived from any other but Him, who is able to establish him who standeth that he stand perseveringly, and to restore him who falleth:-let no one herein promise himself any thing as certain with an absolute certainty; though all ought to place and repose a most firm hope in God's help. For God, unless men be themselves wanting to His grace, as he has begun the good work, so will he perfect it, working (in them) to will and to accomplish. Nevertheless, let those who think themselves to stand, take heed lest they fall, and, with fear and trembling work out their salvation, in labours, in watchings, in almsdeeds, in prayers and oblations, in fastings and chastity: for, knowing that they are born again unto a hope of glory, but not as yet unto glory, they ought to fear for the combat which yet remains with the flesh, with the world, with the devil, wherein they cannot be victorious, unless they be with God's grace, obedient to the Apostle, who says; We are debtors, not to the flesh, to live according to the flesh; for if you live according to the flesh, you shall die; but if by the spirit you mortify the deeds of the flesh, you shall live.

And here is the Catechism of the Catholic Church (#2005--footnotes removed) on the assurance of salvation:

Since it belongs to the supernatural order, grace escapes our experience and cannot be known except by faith. We cannot therefore rely on our feelings or our works to conclude that we are justified and saved. However, according to the Lord's words "Thus you will know them by their fruits" - reflection on God's blessings in our life and in the lives of the saints offers us a guarantee that grace is at work in us and spurs us on to an ever greater faith and an attitude of trustful poverty.
A pleasing illustration of this attitude is found in the reply of St. Joan of Arc to a question posed as a trap by her ecclesiastical judges: "Asked if she knew that she was in God's grace, she replied: 'If I am not, may it please God to put me in it; if I am, may it please God to keep me there.'"

It must be kept in mind that assurance of salvation is not an all-or-nothing affair. Final perseverance is a gift of grace, and it cannot be presumed on as if we have a right to it, but at the same time God's grace works in us in a natural and organic way in which early attainments in sanctification lead to later ones. In this way, sanctification is much like every other area of human life. The more we develop certain habits, the more we are likely to live in accordance with those habits in the future. If I have spent a good deal of time and effort to train myself to avoid immoderate anger in my responses to the events of life, I am much less likely to have an outburst of such anger at any given time, all other things being equal, than a person undisciplined in this area. Most of us do not go around nervously wondering if tomorrow we shall slit our neighbor's throat, not because it is absolutely impossible that we might do so or that we know infallibly that we shall not, but because we recognize that through the training of our habits, beliefs, and values throughout our lives, and because of other traits of our personalities that we have come to know, it is extremely unlikely that we will engage in that sort of activity. Similarly, if, by God's grace, we have become the sort of people who truly love God, who have developed habits of living faithfully for him, of loving our neighbors, of living a life of charity, etc., we have good reason to believe that the growth in grace we have attained will have the effect of helping preserve us from much possible future sin, such that we are unlikely to spend a great deal of time (if any) in a state of mortal sin (that is, in a state of total rejection of a right relationship with God) or to die and end up confirmed eternally in such a condition.

We must also remember that God will never abandon a person who has not abandoned him first. If we choose Christ, we are secure. We cannot go to hell if we die in such a state. If we end up in hell, it will only be because we have deliberately, with full knowledge and consent of our hearts, chosen to turn away from a relationship of love to Christ and from the way of life he has called us to in favor of living life according to our own desires. To do this, we must resist the testimony and pleading of God to our consciences, calling us back to the good path of salvation. We are not talking here about the venial sins we all commit throughout our lives--slips into sinful attitudes and behavior flowing from the fact that we have not yet been made perfect in grace--for these, though evil (and converted souls long to be rid of such evils), do not interrupt the overall commitment of our lives to God. In Catholic language, they do not destroy the overall state of charity (that is, the state of love to God in the commitment of our lives). If we are following Christ, however imperfectly, God will not abandon us.

In short, we cannot know with infallible certainty that we are truly converted or that we are among the elect who will receive eternal salvation.  But we can observe the fruits of God's grace in our lives and so know that we love God and choose to follow him just as we know other things about our internal desires and choices by self-observation, and so be comforted that we are in a state of grace.  And we can observe in ourselves the development and growth of our love towards God and our neighbors, and the strengthening of godly habits and desires, and so have a strong hope that we will  not in the future finally abandon God but will continue to follow to the end, in reliance on the ever-present help of God who continues to build within us grace upon grace.

My wife has written up an interesting article in which she articulates that the transition from Calvinist to Catholic on this point for her was not as large a practical step as I think many Calvinists would assume it to be.  You can find it here.

CONCLUSION

So, to sum up what we have seen, Catholics agree with the soundest Calvinist interpretations of TULI, and they agree with two-thirds of the P as well.  In Calvinist language (though not language that Catholics would typically want to use, since it would be misleading), it can thus be said that orthodox Catholics are four-and-two-thirds-point Calvinists!

As I conclude, I would like to provide an extended quotation from St. Isidore of Seville, who was Archbishop of Seville in the seventh century and is both a saint and a Doctor of the Catholic Church.  I think he sums up well and succinctly the Catholic view of the matters addressed in the TULIP doctrines:

Between the infusion of divine grace and the faculty of the human will there is the following element: the decision stemming from a human choice, which is capable of spontaneously desiring good or bad things. Grace is the free gift of divine mercy, through which we evidence the beginning of a good will and its fruits. Divine grace anticipates man, so that he may do what is good; human free will does not anticipate God's grace, but grace itself anticipates an unwilling person, so that he may want what is good. Because of the burden of the 'flesh,' man finds it easy to sin, though he is slow to repent. Man has within himself the seeds of corruption but not of spiritual growth, unless the Creator, in order to raise him up, stretched his merciful hand to man, who is prostrated as a result of the Fall. Thus, through God's grace human free will is restored, which the first man had lost; in fact, Adam had free will to do what is good, even though he did it with God's help. We obtain our will to do what is good and embrace God perfecting us, thanks to divine grace. We receive the power to begin and to perfect what is good from God, who gave us the gift of grace; as a result of that, our free will is restored in us. Whatever good we do, it is God's, thanks to his prevenient and subsequent grace; but it is also ours, thanks to the [God-made] obedient power of our wills. But if it isn't God's, why do we give him thanks? And if it isn't ours, why do we look forward to the reward of good works? Insofar as we are anticipated by God's grace, it is God's; insofar as we follow prevenient grace to do what is good, it is ours. Nobody anticipates God's grace with his merits, thus making him almost indebted to us. The just Creator chose in advance some people by predestining them, but justly abandoned the others to their evil ways. Thus, the truest gift of grace does not proceed from human nature, nor is the outcome of our free will, but is bestowed only in virtue of the goodness of God's mercy. In fact, some people are saved by a gift of God's mercy which anticipates them, and thus are made "vessels of mercy;" but the reprobates are damned, having been predestined and made "vessels of wrath." The example of Jacob and Esau comes to mind, who, before been [sic] born, and again, after being born as twins, shared the bond of original sin. The prevenient goodness of divine mercy drew one of them to itself through sheer grace, but condemned the other through the severity of divine justice. The latter was abandoned in the mass of perdition, being 'hated' by God; this is what the Lord says through the prophet: "I loved Jacob but hated Esau" (Mal 1:3). From this we learn that grace is not conferred on account of any pre-existing merits, but only because of divine calling; and that no one is either saved or damned, chosen or reprobated other than by decision of God's predestination, who is just towards the reprobates and merciful towards the elect ("All the paths of the Lord are faithful love" Ps 25:10).  [The quotation is from St. Isidore of Seville, Libri Duo Differentiarum, chapter XXII, found in God's Eternal Gift: A History of the Catholic Doctrine of Predestination from Augustine to the Renaissance, by Guido Stucco (Xlibris, 2009), pp. 317-319.]

The doctrines of grace are all about . . . well, grace.  Everything we have is a gift of grace, whether in the order of creation or in the order of redemption and eternal life.  In the order of redemption, everything flows from the righteousness and the sacrifice of Christ.  It has all "been merited for us by the Passion of Christ who offered himself on the cross as a living victim, holy and pleasing to God, and whose blood has become the instrument of atonement for the sins of all men" (Catechism of the Catholic Church #1992).  "With regard to God, there is no strict right to any merit on the part of man. Between God and us there is an immeasurable inequality, for we have received everything from him, our Creator" (Catechism, #2007).  As Canon 12 of the Canons of Orange observes, "God loves us for what we shall be by his gift, and not by our own deserving."  The holiness that God works in us by his grace and the good works that manifest that holiness are indeed truly and greatly pleasing to God, for they are his own works in us.  They are "Christ in us, the hope of glory," to paraphrase the Apostle Paul (Colossians 1:27).  The Catholic Church has even chosen to use the term "merit" to refer to the righteousness that is a gift of God to us in Christ.  God's work in us "merits" God's positive regard--that is, it warrants God's favor, for he cannot but be pleased with his own holiness, the work of his Spirit, the image of his own Son in us, mirrored back to him.  But we have nothing to boast of, for, as the Church says to God, following the apt words of St. Augustine, "You are glorified in the assembly of your Holy Ones, for in crowning their merits you are crowning your own gifts" (Catechism, heading before #2006--footnote removed).  "The saints have always had a lively awareness that their merits were pure grace" (Catechism, #2011).

Our salvation is not something we have produced or earned by our own goodness or our own works, but from first to last is a free, undeserved gift to us from the grace of God through our Lord Jesus Christ, who lived a life of righteousness, suffered and died, rose again from the dead, and intercedes for us in heaven in order to merit and procure for us this blessing.  This is the very heart of the doctrines of grace, and it is something both Catholics and Calvinists share.  On this 500th anniversary of the Protestant Reformation, may both sides learn better to see these great truths mirrored in each others' traditions and to rejoice and give glory to God for it.

Here you can find an article on the Catholic doctrines of predestination and efficacious grace that goes deeper and fuller in some areas than I have gone here.  For a more basic overview of the Catholic doctrine of salvation in general, which also contains links to more specific topics (like indulgences and purgatory, for example), see here.  For some thoughts on the Protestant doctrine of "justification by faith alone" and how Catholic theology relates to it, see here.  For those who are wondering how the Catholic school of thought known as Molinism fits into all of this, see herehere, and here.  For a look at the heresy of Jansenism and the Catholic Church's response to it, which sheds further light on the issues discussed here, see here.

Sola Gratia!  Soli Deo Gloria!