Tim Troutman (formerly known as "The God Fearin' Fiddler") of The God Fearin' Forum has responded to my latest discussion of Eucharistic theology and Aristotle. Perhaps I have not been very clear. Whatever the case, Tim persistently misunderstands both my claim and my argument for it. I am going to try to make what I am claiming very clear here:
The doctrine of transubstantiation, as expounded by Trent, is rendered incoherent by any system of metaphysics sufficiently different from Aristotle's.
Now that I've cleared that up (I hope), let me further explicate my claim and argue for it again. In case you've forgotten, here is my claim:
The doctrine of transubstantiation, as expounded by Trent, is rendered incoherent by any system of metaphysics sufficiently different from Aristotle's.
The God Fearin' Fiddler has a post up on the historical significance of transubstantiation which has led to some interesting discussions. The principle problem with this post and the discussion that follows it, however, is that no one seems to understand the difference between transubstantiation and the Real Presence. Unfortunately, I'm not an expert on this either, but I do think I know enough to clear up some historical and metaphysical confusion. I am going to use two principal sources - session 13 of the Council of Trent, and the relevant article from the Catholic Encyclopedia - to explain the historical development and specific content of the doctrine of transubstantiation, and then attempt to show two things: (1) no such doctrine is affirmed by Ambrose in the passage the Fiddler likes to quote in this connection, and (2) it would be very difficult for Christians with strong Platonist leanings, such as Clement of Alexandria, Augustine, and most early Christian theologians, to even make sense of this doctrine, which renders it highly unlikely that they implicitly accepted it, or that they would have accepted it had it been explained to them.
Let us begin with an outline of the history. From the beginning, Christians used the words Christ himself used in describing the Eucharist. Christ himself said "this is my body" and "this is my blood." This is in essentially all of the records of the words of institution, including 1 Corinthians 11:23-29, the passage most churches read before serving the Eucharist. Christ also speaks this way in John 6, which is one of the most important texts on the theology of the Eucharist.
Now, all Christians, including even Zwingli, have used and still use this language in describing the Eucharist, so it is important to note that if Zwinglian or similar interpretations will work for the text of the New Testament, they will also work for most writers who merely adopt the New Testament's language and don't attempt to describe it in any more detail. Zwingli specifically argued for a symbolic interpretation by pointing out all the places in Scripture where "is" is used to mean "signifies." There appears to be a more or less uncontestable example of this even in the words of institution themselves, as they are recorded in Luke. Jesus says "this cup is the new covenant" (Luke 22:20, emphasis added), but the cup clearly isn't actually the new covenant (how could it be?). Rather, it is the sign and seal of the new covenant. I don't think that either Catholic and Orthodox believers, who like to interpret the words of institution literally, or fundamentalists, who like to interpret everything but the words of institution literally, would want to say that the cup literally is the new covenant.
I am not an expert on patristics (though I am working on it), but I suspect that most of the fathers, especially the earlier ones, simply used the same language as Christ and didn't provide or attempt to provide much further analysis. The question at issue here doesn't hinge on whether we affirm these words to be true. All Christians agree on that. We all agree that these words express some important truth; we don't agree about what truth they express. (Actually, there is some agreement, but there is a lot of disagreement about the details.)
That said, a case can probably be made that many of the fathers explicitly affirmed the doctrine of the Real Presence (certainly at least a few of them did), and that no writings survive from an otherwise orthodox writer in the early period of Christianity who denies this doctrine. The doctrine of the Real Presence is simply the claim that these words are to be interpreted literally: the bread is the body of Christ and the wine is the blood of Christ. In the Eastern Orthodox Church, any attempt at further analysis meets with suspicion. However, as we shall see, the Roman Catholic Church has not only given a metaphysical theory of this doctrine, but has elevated that theory to the status of dogma (that is, all members of the Church are in principle required to assent to it).
According to the Catholic Encyclopedia article, transubstantiation properly so-called (at least the details of the theory) is a uniquely Western doctrine. The word was first used by Hildebert of Tours around 1079. Note that this is contemporary with Anselm, the first of the Scholastics, but before the wide availability of the words of the Arab Muslim philosopher Ibn Rushd (aka Averroes) and through him the works of Aristotle in the West. This will become significant later.
Of course, the history of the word is not a history of the doctrine. I have already outlined the doctrine of the Real Presence (it really is that simple). The Catholic Encyclopedia states that "the Catholic doctrine of Transubstantiation sets up a mighty bulwark around the dogma of the Real Presence and constitutes in itself a distinct doctrinal article, which is not involved in that of the Real Presence, though the doctrine of the Real Presence is necessarily contained in that of Transubstantiation." So when did this distinct doctrine develop? Before or after the use of the word? Unfortunately, I haven't been able to find an answer to that question, and I don't know enough about Anselm and friends to know whether the philosophical commitments of the 11th and 12th century Western Christian philosophers and theologians left room for full transubstantiation. However, the Catholic Encyclopedia informs us that the word first entered Catholic dogmatic definitions at the Fourth Lateran Council in 1215, but the text of that council says only "[Christ's] body and blood are truly contained in the sacrament of the altar under the forms of bread and wine; the bread being changed [Lat. transsubstantiatio] by divine power into the body, and the wine into the blood, so that to realize the mystery of unity we may receive of Him what He has received of us." Here we do have the word "form" (presumably Latin "forma") which is often a synonym of "species", a Scholastic/Aritotelian technical term used in later discussions of the doctrine. Nevertheless, since outside the technical jargon of scholasticism, "forma" just means "shape" and "species" just means "appearance," in order to show that the Fourth Lateran Council actually affirms transubstantiation as we know it today, rather than just using the word, it would have to be shown that the word already had the present day meaning. On the other hand, the word itself would seem to have some Aristotelian baggage (I promise I'm about to explain all of this - I apologize if anyone has to read this long post twice due to my poor organization): the bread and wine are not trans-formed - they retain their original form. Rather they are trans-substanced. The form remains the same, but the substance changes. This is the essence (that's another loaded term in Aristotle/Aquinas talk) of the doctrine. So it is probably affirmed by the Fourth Lateran Council.
At any rate, it is quite clear in the Council of Trent in 1563. Here are some excerpts from the thirteenth session (translated by Philip Schaff):
Chapter I ... after the consecration of the bread and wine, our Lord Jesus Christ ... is truly, really, and substantially contained under the species of those sensible things ...Chapter IV On Transubstantiation. And because that Christ, our Redeemer, declared that which he offered under the species of bread to be truly his own body, therefore has it ever been a firm belief in the Church of God, and this holy Synod doth now declare it anew, that by the consecration of the bread and of the wine, a conversion is made of the whole substance of the bread into the substance of the body of Christ our Lord, and of the whole substance of the wine into the substance of his blood; which conversion is, by the holy Catholic Church, suitably and properly called transubstantiation.
The Canons anathematize anyone who disagrees with this (Canon II even anathematizes anyone who doesn't want to call it transubstantiation!), but don't really add anything.
Here is the metaphysical background: Aristotle was a proponent of what is called a "hylomorphic" metaphysics. That is, he affirmed that material objects were made up of "matter" (Gr. hylas) and "form" (Gr. morphos). There is a lot more complexity than this, but this is the basic idea. This is related to his distinction between "substance" or "essence" (Gr. ousia) and "accident" (I don't know the Greek word for this). The matter of an object is the stuff it's made out of, and it's form is its shape or organization. For the Scholastics, the Latin "species" seems to have been related to Aristotle's "form" but been more closely related to our cognition (the Catholic Encyclopedia article on this didn't make that much sense to me). Objects also have an essence, which is that in virtue of which it is the thing it is, and various accidents, or properties that could change without the object being destroyed. Often, the essence of an object is thought to be a collection of essential properties; thus I might be essentially human.
For the Scholastic/Aristotelian, the doctrine of transubstantiation is kind of weird, but no weirder than the Incarnation of the Trinity, and, more importantly, it is coherent. It is to be explained as follows: the substances or essences of the bread and wine are fully replaced by the substances or essences of the body and blood of Christ (I'm not sure if the matter is also replaced), but there is no change to the accidents, or to the form/species. Thus it still appears to be bread and wine, but it actually is the body and blood of Christ, since essence is what determines identity. Technically, the bread and wine are not changed into the body and blood, but replaced with the body and blood, since you can't change the essence of a thing and still have that same thing. Let me note that, while I'm not an expert on Aristotle, I suspect he would find it preposterous to claim that the essence of a material object could be replaced with another essence (and thus the material object be replaced with a different object) before our eyes without any perceptible difference in the matter before us.
Now we are going to examine Ambrose, and then the philosophical commitments of Augustine and his fellow Christian Platonists.
The Fiddler quotes Ambrose as saying:
Perhaps you will say, "I see something else, how is it that you assert that I receive the Body of Christ?" And this is the point which remains for us to prove. And what evidence shall we make use of? Let us prove that this is not what nature made, but what the blessing consecrated, and the power of blessing is greater than that of nature, because by blessing nature itself is changed.... [Ambrose discusses miracles performed by the prophets] ...
We observe, then, that grace has more power than nature, and yet so far we have only spoken of the grace of a prophet's blessing. But if the blessing of man had such power as to change nature, what are we to say of that divine consecration where the very words of the Lord and Saviour operate? For that sacrament which you receive is made what it is by the word of Christ. But if the word of Elijah had such power as to bring down fire from heaven, shall not the word of Christ have power to change the nature of the elements? You read concerning the making of the whole world: "He spoke and they were made, He commanded and they were created." Shall not the word of Christ, which was able to make out of nothing that which was not, be able to change things which already are into what they were not? For it is not less to give a new nature to things than to change them.
But why make use of arguments? Let us use the examples He gives, and by the example of the Incarnation prove the truth of the mystery. Did the course of nature proceed as usual when the Lord Jesus was born of Mary? If we look to the usual course, a woman ordinarily conceives after connection with a man. And this body which we make is that which was born of the Virgin. Why do you seek the order of nature in the Body of Christ, seeing that the Lord Jesus Himself was born of a Virgin, not according to nature? It is the true Flesh of Christ which crucified and buried, this is then truly the Sacrament of His Body.
The Lord Jesus Himself proclaims: "This is My Body." Before the blessing of the heavenly words another nature is spoken of, after the consecration the Body is signified. He Himself speaks of His Blood. Before the consecration it has another name,after it is called Blood. And you say, Amen, that is, It is true. Let the heart within confess what the mouth utters, let the soul feel what the voice speaks.
In order to show that Amborse accepts transubstantiation, we have to show that he explains the words "this is my body" by the claim that the form and accidents of the bread remain, but its essence has been replaced by the essence of the body of Christ. Do you see that in the above quotation? I don't see any such thing. Ambrose certainly affirms the Real Presence: he says that if God can become human flesh, certainly he can become bread. He says that we shouldn't be surprised if Christ's body doesn't follow the ordinary course of nature, since God often performs miracles in Scripture, and since even Christ's human birth did not follow the ordinary course of nature. But I see nothing here about form and matter, or about substance and accident, or about species. And I'm not just looking for the words, I'm looking for the content. All Ambrose says is "this may look like bread, but it's actually the body of Christ, and God certainly has the power to make what looks, feels, and tastes like bread into the body of Christ." That is the doctrine of the Real Presence.
The last thing I want to cover is the issue of the Platonist leanings of many of the early fathers, notably the Alexandrians and Augustine. I shouldn't have to take pains to show this, because the Catholic Encyclopedia says, "even Augustine was deprived of a clear conception of Transubstantiation, so long as he was held in the bonds of Platonism." Nevertheless, I will at least try to explain it.
Platonism holds that material objects are what they are in virtue of their "participation" (more literally: "having a share") in a transcendant, changeless, immaterial "form" (not morphos, but eidos or idea, which Aristotle also uses, but in a somewhat different meaning than morphos, I think). You and I are both human because we participate in the form of Human, or, as Plato often says Humanity Itself. The bread is bread because of its relationship to Bread Itself. Things are, of course, generally participants in multiple forms, and everything is a participant in Goodness Itself to a greater or lesser degree because Plato holds to a privation theory of evil (which is where Augustine got it), so anything that had no goodness at all would not exist. Christian Platonists generally want to avoid the idea that the forms are co-eternal with and independent of God, so they say that they exist in God's understanding.
A Platonist does not have a concept of an essence as an Aristotelian does. Furthermore, Plato himself, and I believe most Platonists following him, generally cashes out "participation" in terms of "being patterned after." It is very difficult to see how the bread could change from being patterned after bread to being patterned after the body of Christ without any perceptible change. In what would the patterning consist? How does this object resemble a human body, and how Christ's body in particular? Now, there must be some way of getting this to work, because Father Nicolas Malebranche was a very intelligent Platonist Catholic priest in the 17th/18th century, after the Council of Trent, and he must have come up with something, but I don't know what he said.
At any rate, it is highly unlikely that any Christian Platonist held to anything like transubstantiation prior to Malebranche, and a great many of the early fathers, including, as I have said, the Alexandrian school and Augustine, were Platonists.
The situation is even worse for idealists such as myself (or 18th century Anglican Bishop George Berkeley). We don't believe that there is any such thing as the essence or substance or matter of the bread. All that exists, according to idealism, is what the Scholastics would call the "species." Transubstantiation is thus puzzling for the Aristotelian, more puzzling for the Platonist, and completely incoherent for the idealist. I should also note that most contemporary philosophers don't believe in any of these three theories, but transubstantiation is probably also incoherent for them, since material objects don't have undetectible essences (though they may have essential properties).
Now, a Christian idealist does have to come up with some explanation for the bodily resurrection and be able to say that the body that is raised is in some sense the same body although it is radically transformed in terms of its phenomenal properties. Whatever solution one comes up with for this problem could probably also be used to make sense of the doctrine of the Real Presence. However, this view cannot possibly look anything like transubstantiation, for the reasons discussed above.
In the course of a bit of research on Berkeley's views on the epistemology of religion, I have just come across a little letter Berkeley wrote to one Sir John James, dated June 7, 1741. James was, apparently, an Anglican living in Boston who was considering converting to Roman Catholicism. While for some reason (perhaps because he was Irish) Berkeley is often mistakenly believed to have been a member of the Roman Catholic Church, he was, in fact, a member of the clergy of the Church of England, and wrote against Roman Catholicism on a number of occasions, this being one of them. His writings on the subject are, however, admirably balanced, respectful, and civil as compared with many of the polemics produced by his Protestant contemporaries. The letter to James, published in vol. 7, pp. 143-155 of The Works of George Berkeley, ed. Luce and Jessop, contains some wonderful reflections on individual knowledge and experience of God, the nature and authority of the Church, and the Christian life. Below are some passages that stuck out to me. I've copied quite a lot of text here (hurray for the public domain!) because that much of it was that God and Berkeley's theology is a very neglected topic. Most of the references in brackets are found in Luce's footnotes; a few that Luce missed were added by me.
You observe very justly that Christ's religion is spiritual, and the Christian life supernatural; and that there is no judge of spiritual things but the spirit of God. We have need, therefore, of aid and light from above. Accordingly we have the Spirit of God to guide us into all truth. [John 16:3] If we are sanctified and enlightened by the Holy Ghost & by Christ, this will make up for our defects without the Pope's assistance. And why our Church and her pious members may not hope for this help as well as others I see no reason. That Author of our faith tells us, He that will do the will of God, shall know of the doctrine, whether it be of God. [John 7:17]There is an indwelling of Chirst and the Holy Spirit, there is an inward light
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There is an invisible Church whereof Christ is the head, the members of which are linked together by faith, hope, & charity. By faith in Christ, not in the Pope.
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Men travelling in day-light see by one common light, though each with his own eyes. If one man shou'd say to the rest, Shut your eyes and follow me who see better than you all. This wou'd not be well taken. The sincere Christians of our communion are governed or led by the inward light of God's grace, by the outward light of his written word, by the ancient and Catholic traditions of Christ's church, by the ordinances of our National Church which we take to consist all and hang together. But then we see, as all must do with out own eyes, by a common llight but each with his own private eyes. And so must you too or you will not see at all. And not seeing at all how can you too chuse a Church? Why prefer that of Rom to that of England? Thus far, and in this sense every man's judgment is private as well as ours. Some indeed go farther and without regard to the holy Spirit or the word of God, or the writings of the primitive fathers, or the universal uninterrupt'd traditions of the Church, will pretend to canvass every mystery, every step of Providence, and reduce it to the private standard of their own fancy, for reason reaches not those things. Such as these I give up and disown as well as you do.
I grant it is meet the Law of Christ shou'd like other laws have magistrates to explain and apply it. But then as in the civil State a private man may know the law enough to avoid transgressing it, and also to see whether the magistrates deviate into tyrrany: Even so, in the other case a private Christian may know and ought to know the written law of God and not give himself up blindly tot he dictates of the Pope and his assessors.
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Light and heat are both found in a religious mind duly disposed. Light in due order goes first. It is dangerous to begin with heat, that is with affections. To ballance earthly affections by spiritual affections is right. But our affections shou'd grow from inquiry and deliberation else there is danger of our being superstitious or Enthusiasts. An affection conceived towards a particular Church, upon reading some spiritual authors of that Communion which might have left a bias in the mind is I apprehend to be suspected. Most men act with a byas. God knows how far my education may have byassed me against the Church of Rome ... It is our duty to strive to divest our selves of all byas whatsoever.
Whatever unguarded expressions may be found in this or that Protestant Divine, it is certainly the Doctrine of our Church that no particular church or congregation of Believers is infallible. We hold all mankind to be peccable and errable, even the Pope himself with all that belong to him. We are like men in a cave in this present life seeing by a dim light through such chinks as the divine goodness hath open'd to us. We dare not talk in the high unerring positive style of the Romanists. We confess that we see through a glass darkly [1 Cor. 13:12]: and rejoice that we see enough to determine our practice and excite our hopes.
...There is indeed an invisible Church, whereof Christ is head, linked together by charity, animated with the same hope, sanctifyed by the same Spirit, heirs of the same promise. This is the universal church militant and triumphant: the militant dispersed in all parts of Christendom partaking of the same word and sacraments. There are also visible, political or national churches: none of which is universal ... The members of this universal church are not visible by outward makrs, but certainly known only to God whose Spirit will sanctifie and maintain it to the end of time.
The church is a calling ekklesia. Many are called by few are chosen. [Matt. 22:14] Therefore there is no reckoning the elect by the number of visible members. There must be the invisible grace, as well as the outward sign; the spiritual life and holy unction to make a real member of Christ's invisible church. The particular churches of Jersualem Antioch Alexandria Rome &c have all fallen into error. And yet in their most corrupt and erroneous state I believe they have included some true members of that body whereof Christ is head, of that building whereof He is the corner stone. [Eph. 2:20] Other foundation shall no man lay, but on this foundation there may be superstructures of hay stubble [1 Cor. 3:11-12] and much combustible trash without absolutely annihilating the church. This I take to have been evidently the case. Christ's religion is spiritual and supernatural, and there is an unseen cement of the faithful who draw grace from the same source, are enlightened by the same father of lights [James 1:17] and sanctified by the same Spirit. And this, although they may be members of different political or visible congregations, may be estranged or suspected or even excommunicate to each other. They may be loyal to Christ however divided among themselves.
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But perhaps you will say there is need of an infallible visible guide for the soul's quiet. But, of what use is an infallible guide without an infallible sign to know him by? We have often seen Pope against Pope and Council against Council. What or whom shall we follow in these contests by the written word of God, the Apostolical traditions, and the internal light of the logos that irradiates every mind but is not equally observed by all?
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As Plato thanked the gods that he was born an Athenian, so I think it a peculiar blessing to have been educated in the Church of England. My prayer nevertheless and trust in God is, not that I shall live and die in this church, but in the true church. For, after all, in respect of religion our attachment shou'd be only to the truth.
The God Fearin' Fiddler has a post up on why Protestants are offended by Mariology. This was one of the issues that came up in our previous debate, so I would like to address it briefly here. Before I do so, I want to make a few preliminary remarks. The first is that the assertion that Mariology is offensive to Protestants contains a terminological mistake, but it is a mistake that is also made by many Protestants. "Mariology" is the branch of theology that deals with Mary. Protestants are not offended by this subject of study. In fact, there is such a thing as "Protestant Mariology." I shall have more to say about this shortly, but for now let me give as an example that Protestants are not Nestorian: we do indeed believe that Mary was theotokos - she carried God Himself in her womb and gave birth to him. This is a statement of 'Mariology' and one which is not offensive to Protestants. Now the particular doctrines of Catholic and Orthodox Mariology, and the practices associated with them, are indeed offensive to Protestants (or, at least, Protestants disagree with them), so we do still have something to discuss. Second, I'd like to point out that in our discussions so far it has become clear that when the Fiddler was a Protestant, he was more 'Reformed' than I am. By 'Reformed' (in scare quotes) I mean two things: first, that on certain issues (which issues these are will, I hope, emerge in coming discussions) his version of Protestantism was further away from Catholic views than mine (of course, on other issues - sacraments, for instance - Presbyterians are closer to Catholicism than I am); second, I mean that his views were more similar to those of Calvin and of prominent Calvinists of later times. As a result, we have sometimes in this discussion found ourselves in unexpected agreement (though I'm not sure we've always realized it).
Having said those two things, let me proceed to the task at hand, which is a brief (I hope) examination of the Protestant view of Mariology and it's differences from the Catholic view.
As I have already stated, Protestants are not Nestorians: we do affirm that Mary gave birth to God. While, as the Council of Ephesus affirmed, Mary is indeed theotokos (lit. "The God-Bearer" - where "bear" means "to give birth to" unlike in the name "Christopher," sometimes translated "Christ-Bearer," where "bear" means "to carry") , many Protestants have objected to the traditional English translation "Mother of God" (from the Latin translation Mater Dei) as it has seemed to some to imply that Mary is the ontological source of God (though clearly no one has ever intended the phrase in this way) or, less radically, that some continuing relationship between Mary and the Godhead is present as a result of her role as theotokos. To this latter claim more attention will be given shortly, but suffice it to say that we all agree that Mary gave birth to God in the flesh.
Now, Protestants have been cautious in making any statements about Mary probably due to what they see as the excesses of Catholicism and so, unfortunately, not much thought is devoted to her in most Protestant circles. There is, however, an urgent need for Protestants to recover the theology of the Magnificat (Luke 1:46-55), and, of course, in the preceeding passage, Elizabeth says to Mary "Blessed are you among women, and blessed is the fruit of your womb!" (Luke 1:42) Compare this to the text of the traditional Ave Maria:
Hail Mary, full of grace, the Lord is with thee; blessed art thou among women, and blessed is the fruit of thy womb, Jesus.
Holy Mary, Mother of God, pray for us sinners, now and at the hour of our death. Amen.
(It is also of interest that Elizabeth says eulogeo in v. 42, but Mary says makarioo in v. 48 - but that's a discussion for another time.)
Furthermore, many (though not all) Protestants have affirmed a tradition regarding the interpretation of 1 Timothy 2:15 which would translate it as something like "But she [i.e. Woman in the abstract] will be saved through the birth of a Child, if they [women, individually] continue in faith and love and holiness with prudence." Obviously, Mariology won't solve every difficulty with this extremely puzzling verse (at least as confusing as the passage immediately preceding it!), but the idea, which is developed in many of the Church Fathers, is that Mary is, in some sense, the new Eve (just as Christ is the new Adam - Romans 5:12-21). Now, this must be carefully developed in a Protestant direction: it is (for reasons I don't particularly understand) Adam who is responsible for the Fall, but Eve took the fruit first, and handed it to him. So there is an idea here of a reversal of sorts. The first Eve took the fruit first, and handed it to the first Adam, and he fell. The second Eve suffered first (in the pain of childbirth - contrary to some ancient and Medieval writers who said that since Jesus was free from the curse of sin his birth must have been painless) in order to bring the second Adam into the world, so that, just as the first Eve put the first Adam in a position to fall, the second Eve put the second Adam in a position to redeem. Nevertheless, it is the first Adam who is responsible for the Fall, and the second Adam who brings about redemption. Mary's suffering does not accomplish or in any way contribute to redemption.
It is also critically important the Christ is unique. No one else could have brought about our salvation. But God could have chosen someone else than Mary, just as he could have chosen someone else than Abram. He could not have chosen someone else than Jesus. Mary, like Abram, is to be praised for her obedience in the face of bizarre divine commands, and for her faith that God would bring about his promise. Protestants should not shy away from making these kinds of assertions.
I am told that Calvin even saw Mary as a type of election. That is, like Mary, each of us is chosen by God to bring Christ into the world around us in our lives and actions; like Mary, we are undeserving.
It will be noted that none of the above squares well with the doctrine of the Immaculate Conception. There is a further problem with that doctrine as well: it places Christ at a further remove from humanity. By calling Mary a perfect vessel and denying that Christ was born through any ordinary woman, Christ is separated from us not only by his own perfection, but by the perfection of his mother. And how is his mother free from original sin? Some Medieval Catholic writers claimed that this was because Saint Anne (the mother of Mary) was also a virgin at the time of Mary's birth, so that there was no male line to transmit Original Sin, but this was eventually repudiated by the Church (at least that's what Wikipedia says). Furthermore, this contradicts what Paul says throughout Romans (and what is taught through the rest of Scripture) about all humans being sold under sin. Furthermore, it should be noted that, in Luke 1:28 the word translated 'favored' or 'highly favored' in most translations is the Greek charizomai, so that Mary is addressed literally as "woman to whom grace is shown;" but grace (Gr. charis) is by definition undeserved! The Scripture does not treat Mary as "immaculate" but as graciously chosen by God.
A related doctrine is the doctrine of the perpetual virginity of Mary. This one is very common from very early times in the history of Christianity, and it doesn't explicitly contradict any Scripture, nor, I suppose, does it have any particular theological problems, but it requires highly unnatural interpretations of Scripture in a number of places. Firstly, right at the beginning of the New Testament in Matthew 1:25 it says that Joseph "did not know her [Mary] intimately until she gave birth to a son." This is not an explicit contradiction, but in the most straightforward interpretation it implies that he did know her intimately after she gave birth (and this is where Catholics start to be offended by Protestant Mariology!). Second, there are all the references to Jesus' siblings (Matt. 13:55-56, Mark 6:3, etc.). Catholics usually point out (rather questionably) that adelphos can also mean cousin or (less questionably) half-brother or step-brother or brother-in-law (the last of these is, of course, not relevant). So the claim that these were Jesus' cousins doesn't hold any water, but the half-/step-brother claim (that is, the claim that the children were Joseph's by a previous marriage) is a possible interpretation, although it is not the most straightforward one.
The final and, in my view, most important consideration is simply that Mary and Joseph were married. Paul gives the following moral command: "A husband should fulfill his marital duty to his wife, and likewise a wife to her husband. A wife does not have authority over her own body, but her husband does. Equally, a husband does not have authority oover his own body, but his wife does. Do not deprive one another - except when you agree, for a time, to devote yourselves to prayer. Then come together again; otherwise, Satan may tempt you because of your lack of self-control." (1 Cor. 7:3-5) It is true that the next verse says "I say this as a concession, not a command," but that most likely refers back to verse 2, where he talks about people marrying at all. Even within Catholicism, a marriage is only valid if it is consummated by intercourse. How, then, could Mary and Joseph be married? And, make no mistake, they were married: the angel commanded Jospeh, "don't be afraid to take Mary as your wife" (Matt. 1:20). There is no ambiguity here. So the doctrine of perpetual virginity is no good Biblically. It probably comes from the similarly unbiblical idea that sex is somehow evil, which was popular among certain segments of early Christianity and in late Medieval (and later) Catholicism.
The other doctrine in this cluster is the Assumption. I have no argument to make against that, other than that it isn't recorded in Scripture. Nothing that happened to me today is recorded in Scripture, but it still happened. Elijah and Enoch were 'assumed' into heaven bodily. In short, my answer to this one is "whatever." I see no good reason to believe that it happened, but I suppose it could have.
Of course, none of these doctrines is the central issue. The really central issue is the differing treatment of the Communion of Saints, and the practice of 'veneration' of saints and icons, as well as prayer to saints. The Fiddler mentions that, during the course of his conversion, he discovered that he was comfortable with prayers to Michael the Archangel for protection, but not prayers to Mary. I suggest that this is actually not because of the general Protestant discomfort with Mary, but because there is good Biblical/theological reason to suppose that Michael the Archangel and hear us and does protect us, but no similar reasons with regard to Mary.
This post has already gotten quite long, so I'm not going to include general arguments about prayers to saints. I've already dealt briefly with the issue of the supposed distinction between 'worship' and 'veneration' in my post on icons. I'm not convinced that the distinction is real, and I think this is the real reason why even some informed Protestants (and not only the ignorant ones) claim that Catholics worship Mary. I would not say this in the context of a discussion with a Catholic, but only because it would be begging the question: we all agree that worshiping Mary would be wrong, but we disagree on whether official Catholic practice (what actually happens in, e.g., Latin America is another story altogether) constitutes the worship of Mary. That, as I have said, is a topic for another post.
I have recently been participating in a little debate over at The God Fearin' Forum on some of the issues of Church history (primarily history of doctrine) that are significant to Protestant-Catholic (and Orthodox!) disagreements. I encourage you all to head over and read the debate so far, and perhaps someone more knowledgeable than I will jump in! Later today (if I have a chance) I'm hoping to get a case put together for the historical foundations of Sola Scriptura (to show, contrary to GodFearinFiddler's claim, that this doctrine was around prior to the invention of the printing press). If anyone feels like beating me to the punch on that, consider yourself invited.