Corpusso Meusso

Today is the memorial for St. Bernardino of Siena (1380-1444), often called the Apostle of Italy. He became a Franciscan Observant -- a strict form of Franciscan -- in 1403, and went on to become an extraordinarily famous itinerant preacher. His homilies are very vivid, and crafted to speak to the common people rather than to the elite or dainty, but they are also quite rigorously thought through, drafted and revised extensively before they were ever delivered. He was especially devoted to the Holy Name, and is a reason for the common iconographic image of the letters IHS on a blazing sun, and was even investigated for heresy over it (he was cleared, of course). They repeatedly tried to make him a bishop; he repeatedly refused, although they eventually got him to be Franciscan Vicar General.

The following is from a sermon on wives and marriage:

So for example of a priest who undertakes to do his priestly work, that is, to consecrate the Lord's Body, and knows not the manner nor the words of consecration, how would you hold this man excused? If, indeed, he sins even in that he does not as he should. Hear now what befel once upon a time; for this is to our present point. There were two priests who spake together, and one said unto the other, "How do you say the words of consecration for Christ's Body? "I" (said the other) "I say Hoc est Corpus meum" Then began they to dispute one with other: "You say not well"-"Nay, it is you who says ill"-and, as they disputed thus, there came another priest to whom they told the whole matter, and who said: "Neither one of you says well, nor the other, for the true words are Hoc est corpusso meusso": and proceeded by demonstration: "You see how he says corpusso, wherefore the adjective should be meusso; therefore (I say) henceforth say you nothing else but: Hoc est corpusso meusso." To which speech the others consented not: wherefore they accorded together to a parish priest near by, going to him of set purpose and laying the case before him. Then the parish priest answering "Ha, what needs all this ado? I go to it right simply; I say an Ave Maria over the Host!" - Now, I ask you, are these men excused? See you not that they make men adore a God a mere piece of bread? Be sure that each of them commits a most deadly sin, seeing that it was their bounden duty to do after the manner which Jesus Christ has ordained to Holy Church. So I say also that, whatever a man does, it is his bounden duty to know all that pertains to that thing.

Alas, I fear we live in an age of corpusso meusso.

Evening Note for Friday, May 19

Thought for the Evening: Saint Teresa of Avila and Rene Descartes

Christia Mercer has an interesting paper discussing the possibility that St. Teresa of Avila might be an influence on Descartes. (It has been fortuitously making the rounds while I've been reading St. Teresa, due to this article, which overstates things a fair amount. I think I first saw notice of the article here, but the most extensive discussion has been in the comments at the Leiter Report.) She primarily focuses on arguing that Descartes's use of the notion of an evil deceiver is anticipated by St. Teresa, especially in the Interior Castle. In particular, she thinks they share what she calls the deceiver strategy, composed of the following features, slightly paraphrased:

(1) The meditator recognizes that many of her beliefs need to be reevaluated.

(2) The meditator sees the need to set aside her beliefs as a first step in the discovery of fundamental truths.

(3) The only way to do this is to refrain from assenting to beliefs about the external world.

(4) When the meditator commits to this, however, the beliefs return and tempt her.

(5) A deceiving demon confounds the meditator and impedes her progress.

(6) The meditator needs to rethink her way forward by means of self-knowledge.

As I have noted in discussing Hume and Buddhism, there are a number of questions that have to be considered in an argument like this. We have (a) the question of what, exactly, the structural parallel is; (b) the assessment of our causal evidence, particularly with regard to available causal paths; (c) causal inference in order to determine whether the reason for the parallel is influence, convergence, objective coincidence, or an artifact of interpretation; (d) assessment of what, exactly, this illuminates in either.

(a) The six-element structure Mercer identifies is interesting. It is true that both St. Teresa and Descartes are concerned with self-knowledge, and that the question of deception is often a major issue for both. The emphasis on belief is a possible issue, since St. Teresa is actually concerned with the whole of life, and not just belief. But it is true, as Mercer says, that St. Teresa's emphasis on self-knowledge means that her conception of the problems often has clear epistemological elements in it.

The structure is also notably pitched at a very general level. (3) is the one that worries me the most on this; I'm not wholly convinced refraining from assent to belief is a good way to characterize what she is talking about, even despite the epistemological aspect of her discussion. And if you get less general than this, I think the differences between what St. Teresa is doing and what Descartes is doing are rather significant. But it is true that we have certain basic themes, linked together, in some kind of order: the need to overcome oneself, the issue of deceptive power, and the importance of entering into oneself in order to deal with these. This is arguably enough to be going on, although the generality forces one to a certain modesty in one's conclusions.

(b) Mercer does an excellent job of identifying in a very concise way the evidence for available causal pathways -- the Jesuit curriculum in which Descartes was taught had a component concerned with spirituality; St. Teresa had close connections with the Jesuits; the Jesuits had been active in pressing for her beatification, which occurred in 1614 while Descartes was at La Flàche; her writings had a surge of popularity after her canonization in 1622; and people around Descartes were reading her. On its own these things are enough to establish a possible causal pathway; indeed, they would be sufficient to make the pathway probable if the parallel were stronger and more precise than Mercer shows it to be.

(c) I think we can reasonably rule out that the parallel is just an artifact of interpretation -- there is no doubt that St. Teresa and Descartes both put self-knowledge and knowledge of God at the center of their projects, that they both often have explicitly epistemological concerns (Mercer does not go into detail, but anyone who reads St. Teresa knows that she has extensive discussions of how you can know that your experiences of God are genuine), they both consider the question of deception by a greater power, and so forth. We can also rule out mere coincidence, in part because in this context, given this topography of evidence, anything one could propose as an argument for coincidence would be a much stronger argument for convergence based on a common context -- both St. Teresa and Descartes can be considered Augustinian, broadly speaking, and both clearly get much of their conception of self-knowledge from Augustine in one way or another, so the common environment is rather robust here, and the features of the parallel are quite clearly linked to the common environment. Even if Descartes developed his ideas entirely independently of anything in St. Teresa, he is developing common themes in a shared tradition under shared background pressures.

It is with deciding between influence and convergence that we run into the limits of our evidence. All of the themes Mercer notes are in fact Augustinian -- and St. Augustine's parallels with Descartes are far more extensive than St. Teresa's seem to be, as a great deal of the research on parallels between Augustine and Descartes has shown. This is a problem because St. Augustine's influence clearly swamps the field, both contextually (he is far and away the single most important philosophical influence in seventeenth century France) and in terms of Descartes himself. If St. Teresa is an influence, untangling that influence from some other path back to Augustine is not a straightforward task. I think Mercer would have to put the emphasis on the order of the six features. But to some extent the order is a natural growth out of any desire for improvement -- we recognize the need for change, we put aside what is problematic, we discover new difficulties in doing so, we overcome those impediments. The shared distinctives in the case of St. Teresa and Descartes are self-knowledge and the worry about an evil deceiver. That these have similar places in the thematic order is suggestive. But the underlying factors are fairly different: St. Teresa is concerned with evil deceivers because she had difficulty convincing people that she wasn't being deceived by the devil, as she notes in her Life; Descartes is interested in it as a device for pressing skepticism to its farthest possible extent. There is an undoubted similarity; but it is a loose one. Given everything, while the available causal pathways and the loose similarity make it impossible to rule influence out, it seems the evidence currently favors convergence rather than influence.

(d) Which is not a minor thing; one does not have to argue that St. Teresa is a direct influence on Descartes in order to have what one needs in order to argue that a comparison of St. Teresa and Descartes is potentially illuminating. This Mercer leaves for further inquirers, and this, I think, she has shown is a worthwhile project. St. Teresa has prior connections of note with other philosophers -- St. Edith Stein's philosophical work on the self being the most obvious because it is the most explicit case of St. Teresa directly influencing a philosophical discussion -- but another line of possible inquiry is always worthwhile when it is sufficiently established.

Various Links of Interest

* Ed Yong summarizes the recent lines of research suggesting that the human sense of smell is actually quite good.

* Edmund Waldstein, O.Cist., The Object of the Moral Act

* King Willem-Alexander of the Netherlands has, for the past twenty-one years, been working occasionally as an airline pilot, incognito, as a hobby.

* Maurice Baring, The Ikon, is a short story well worth reading: a freethinker learns the price of mixing deities.

* Tim O'Neill discusses the charges against Giordano Bruno.

Currently Reading

Teresa of Avila, The Life of Saint Teresa of Avila by Herself
Teresa of Avila, The Interior Castle
Satischandra Chatterjee, The Nyaya Theory of Knowledge
Vladimir Soloviev, The Justification of the Good

Elements of Modal Logic, Part VII

Part VI

Sometimes when we are reasoning, we are taking something as a reference point that is part of what we are talking about. For instance, if we are talking about time, we might talk about now; if we are talking about location, we might talk about here. 'Now' is a time, albeit a special one; 'here' is a location, although it is a special one. None of our rules so far take this kind of thing into account. In everything we've done so far, our Reference Table is not assumed to be itself one of the tables we are talking about. But sometimes we want our Reference Table to be one of the tables described in the Reference Table; we want it to include itself. This brings us to our next rule, which we might call the reflexivity rule. Rules like it are often called T, or sometimes M; I will call it M:

(M) □ on the Reference Table means that what it applies to is on the Reference Table.

Suppose we are thinking about books on your shelf. We can represent each of them as a table. Suppose you keep track of the books on your shelf by describing them all in a book, which you keep on that shelf. We can call it your Inventory Book. Your Inventory Book is working in a way that can be represented by a Reference Table. We might look at a line in the Inventory Book and discover that it says every book on the shelf mentions other books; this would give us the following Reference Table:

REFERENCE TABLE (=INVENTORY BOOK): Books on the Shelf
□ (Other books are mentioned.)

Since our Inventory Book is one of the books the Inventory Book itself describes, and □ here tells us that the statement following it is true of every book on the shelf, and thus every book described by the Inventory Book, we know that the Inventory Book mentions other books.

We use this kind of rule quite a bit. So, for instance, we can all see that if something is always true, it is true now, and that if something is found everywhere, it is found here, and that if everybody has a man-eating lion for a pet, I have a man-eating lion for a pet. These are all straightforward uses of the reflexivity rule. And it doesn't matter what the reference point is; perhaps my reference point is not now but the beginning of the world, not here but there, not me but you: it all works the same.

Since our rules are independent, we may use both (D) and (M) or only one. We've seen already that there are many cases in which (D) on its own will suffice; 1234D modalities are very common. 1234M modalities are much less common. The reason is that they are a little odd. They pick a reference point, and doing this makes it so that the Reference Table can talk about itself, (M) on its own is not enough to make the Reference Table a real table; for instance, it might just be something that could be a real table. So, for instance, if my Reference Table is The Day Pigs Fly, and it is true on that day that □p, where p is some claim about the way things are, (M) tells us that p is true on the day pigs fly; but it doesn't tell us that there is actually any real day that is the day pigs fly. (D) tells us that there is a real table somewhere; (M) on its own doesn't -- it just tells us what will be true on the Reference Table if the Reference Table actually exists.

While 1234M modalities seem to be found only in unusual cases, 1234DM modalities are much more common, because in 1234DM, the modalities work just like they do in the easy-to-use 123D modalities, but now, thanks to (M), you have the ability to pick a special reference point like 'here' or 'now'. This makes them very powerful and flexible. Just a few examples of cases in which we often like to use them:

□	reference point	◇
everybody	me	somebody
everywhere	here	somewhere
always	now	sometimes
necessary	true	possible

But, again, even with the same Box and Diamond, we can often pick different reference points. Any point in time can be a reference point for times, and so forth. This raises the question: Can we use more than once reference point at a time? And the answer is a very definite yes, and that gets us into a lot of interesting things. But before we get there, we should take a look at how (M) affects the square of opposition, and also at some of the things 1234DM modalities let us easily do.

Part VIII

Little Veil for So Great Mystery

To a Daisy
by Alice Meynell

Slight as thou art, thou art enough to hide
Like all created things, secrets from me,
And stand a barrier to eternity.
And I, how can I praise thee well and wide

From where I dwell—upon the hither side?
Thou little veil for so great mystery,
When shall I penetrate all things and thee,
And then look back? For this I must abide,

Till thou shalt grow and fold and be unfurled
Literally between me and the world.
Then I shall drink from in beneath a spring,

And from a poet’s side shall read his book.
O daisy mine, what will it be to look
From God’s side even of such a simple thing?

Things You Can't Compare

[In bracketed italics, I've added some of the remarks of commenters who offer corrections and additions, in case the comments are ever lost. Thanks to them for their comments!]

I was thinking about this today after reading the Spanish expression, No hay que confundir la velocidad con el tocino, one must not confuse speed and bacon. In English, of course, we say that you can't compare apples and oranges, and this seems to be known in French and Spanish as well, although in French it tends more often to be apples and pears (des pommes et des poires), a pair also used in Spanish (you can't add pears and apples, no hay que sumar peras y manzanas). The Portuguese reject the comparison of oranges and bananas (laranjas com bananas).

I don't know how accurate it is (all of the above I can confirm), but the Wikipedia article on apples and oranges gives a list of expressions for other languages:

Some languages use completely different items, such as the Serbian Поредити бабе и жабе (comparing grandmothers and toads), or the Romanian baba şi mitraliera (the grandmother and the machine gun); vaca şi izmenele (the cow and the longjohns); or țiganul şi carioca (the gypsy and the marker), or the Welsh mor wahanol â mêl a menyn (as different as honey and butter), while some languages compare dissimilar properties of dissimilar items. For example, an equivalent Danish idiom, Hvad er højest, Rundetårn eller et tordenskrald? translates literally as What is highest, the Round Tower or a thunderclap?, referring to the size of the former and the sound of the latter. In Russian, the phrase сравнивать тёплое с мягким (to compare warm and soft) is used. In Argentina, a common question is ¿En qué se parecen el amor y el ojo del hacha? which translates into What do love and the eye of an axe have in common? and emphasizes dissimilarity between two subjects; in Colombia, a similar (though more rude) version is common: confundir la mierda con la pomada, literally, to confuse shit with salve. In Polish, the expression co ma piernik do wiatraka? is used, meaning What has (is) gingerbread to a windmill?. In Chinese, a phrase that has the similar meaning is 风马牛不相及 (fēng mǎ niú bù xiāng jí), literally meaning "horses and cattles won't mate with each other", and later used to describe things that are totally unrelated and incomparable.

[Mikhail says, on the Wikipedia Russian claim, "Nobody says that in Russia! The phrase used is - не надо сравнивать божий дар с яичницей - which means 'don't compare God's gift with fried eggs"'... :)"]

[hghandi says, "In Iran there are two phrases used.
آسمون ریسمون کردن
is literally "talking about sky and rope". They only rhyme together (ASEMOUN, RISMOUN) but one is sky the other is rope.
The other phrase is
چه ربطی گوز دارد با شقیقه؟
literally meaning "what is the relationship between fart and temple?" temple as a part of body that is."]

An 1864 text says you can't compare apples and herrings; in 1901 engineers were saying you couldn't compare apples and potatoes; a 1908 text denies you can compare apples with eggs; in 1915 the American Produce Review denied you could compare apples and pears. But it goes back earlier than that; John Ray in his 1670 proverb collection gives four examples of false comparisons: apples and oysters (which Shakespeare also uses in the Taming of the Shrew), four-pence and a groat, nine-pence and nothing, chalk and cheese (the last of which still is occasionally heard).

Everything I've seen suggests that 'apples and oranges', specifically, is an American thing -- after all, we have long had both in immense supply. [Tailz says, "Apples and oranges is used with equal frequency on the British side on the pond too." I think I intended to say that it was of American origin! I've come across British writers using the expression, so my claim was certainly not right, as written, as even I knew. But even the origin claim is speculative.]

I think, though, the general moral to be drawn is that nothing is comparable to apples.

A Tree of White Birds

Today is the feast of St. Brendan the Navigator, best known for the legendary stories told about him in The Voyage of St. Brendan. A summary of an interesting episode from the Voyage, as condensed by John Patrick Crichton-Stuart, the third Marquess of Bute:

On the south shore of this island they found a river a little broader than the ship, and up this they towed her for a mile, when they came to the fountain-head of the stream. It was a wondrous fountain, and above it there was a tree marvellously beautiful, spreading rather than high, but all covered with white birds, so covered that they hid its foliage and branches. (The notion is perhaps taken from a tree loaded with snow.)... And [a bird] said, "We are of that great ruin of the old enemy; but we have not fallen by sinning or consenting; but we have been predestinated by the goodness and mercy of God, for wherein we were created, hath our ruin come to pass, through his fall and the fall of his crew. But God the Almighty, Who is righteous and true, hath by His judgment sent us into this place. Pains we suffer not. The presence of God in a sense we cannot see, so far has He separated us from the company of them that stood firm. We wander through the divers parts of this world, of the sky, and of the firmament, and of the earths, even as other spirits who are sent forth [to minister]. But upon the holy days of the Lord, we take bodies such as Thou seest, and by the ordinance of God we dwell here, and praise our Maker...." And when the bird had so spoken, it rose from the prow, and returned unto the others. And when the hour of evening came, they all began to flap their wings, and to sing as it were with one voice, saying, "Praise waiteth for Thee, O God, in Zion, and unto Thee shall the vow be performed in Jerusalem, through our ministry." And they repeated that verse even for the space of an hour, and the song and the sound of their wings was like harmony (carmen cantus) for sweetness. Then holy Brendan saith unto his brethren, "Refresh your bodies, since this day the Lord hath satisfied your souls by His Divine rising again." ...So by day and by night these birds gave praise to God.'

Music on My Mind

Clamavi De Profundis, "Song of Durin".

Elements of Modal Logic, Part VI

Part V

So far we have considered five rules on the basis of which you might construct a modal logic -- (1) and (2) are defining rules that tell us how to understand Box and Diamond, (3) and (4) are interdefining rules that tell us how Box and Diamond are related to each other, and (D) is the subalternation rule, which tells us that what is true of Diamond will also be true of Box. As noted, one could have different rules in each case -- (1) and (2) are more or less fixed as definitions of Box and Diamond, but you could have variations that introduce qualifications or limitations; (3) and (4) are easily the most common rules for interrelating Box and Diamond, but you could have different rules; and whether or not one accepts (D) depends on what you are trying to say. But it is indeed the case that most modal reasoning uses these rules.

(1) □ applying to anything on the Reference Table means that it would be found on any table there might be.

(2) ◇ applying to anything on the Reference Table means that there is a table on which it is found.

(3) □ is interchangeable with ~◇~.

(4) ◇ is interchangeable with ~□~.

(D) □ includes ◇.

Each of these rules adds a new layer to the character of Box and Diamond. Let's focus on Box for the moment, since Box and Diamond are in many ways parallel. Every rule imposes a division or partition on our possibilities. Rule (1) divides our possibilities into at least two options: Box and Not Box. This could be all we have, but usually what we are applying Box to can be negated as well. That is, we have four possibilities:

Box
Not-Box
Box-Not
Not-Box-Not

Of these, Box is directly opposite to Not-Box -- they contradict each other; and the same is true of Box-Not and Not-Box-Not. so we get the following relationships:

The diagonal lines means 'These contradict each other' or 'These are exact opposites'. The above diagram represents Rule (1) when we are using Nots both before and after Box. You can, of course, do exactly the same thing with Rule (2) for Diamond.

Rules (3) and (4) together make our Box diagram and our Diamond diagram the same diagram, by aligning the corners -- that is, (3) tells us that the □ corners is the same as the ~◇~ corner, and (4) tells us that the ◇ corner is the same as the ~□~ corner. Since each of these has a direct opposite, we can then figure out that □~ corner of the diagram must be the same as the ~◇ corner, and that the ~□ corner must be the same as the ◇~ corner. So we can substitute the Diamond symbols for the Box symbols, and vice versa, whenever we want to do so.

With (D) we get something new. (D) tells us that we can get a ◇ from any □, but, of course, that's one-direction; it doesn't work in the opposite direction. We can represent this by adding an arrow from □ to ~□~, which (4) tells us is the same as ◇, and another arrow from □~ to ~□, for the same reason. But if □ always gives us ~□~, and ~□~ is inconsistent with □~, then □~ and □ have to be inconsistent, too. So if (D) is one of our rules, those also have to have a line between them. We then get the following diagram:

(And, of course, we have to remember that we can substitute Diamonds as long as we follow Rules (3) and (4) in doing so.) Corners separated by the diagonal bars are usually called contradictories. The corners separated by the horizontal bar at the top are usually called contraries. The corners linked by the arrows are called alternates, with the top one being the superalternate and the bottom one being the subalternate. The two bottom corners, which are neither separated by a bar nor linked by an arrow are usually called subcontraries. And, of course, any diagram like this is called a square of opposition. The relations that make it up were first discovered by Aristotle himself; and putting it in a diagram form like the one above goes back at least to the second century, and, because a form was used in a logic commentary by Boethius, became one of the most famous and influential of all logic diagrams. Medieval logicians didn't think in terms of Box and Diamond, but they did recognize you could form this kind of diagram with All and Some, and also with Necessary and Possible, when you are making statements. And you can use the square to think about how different kinds of statements are logically related to other kinds of statements.

Any Box and Diamond that follow Rules (1), (2), (3), (4), and (D) gives us a square of opposition that looks like the above diagram. And any group of concepts which you can relate to each other in the ways given by the diagram above, can be regarded 1234D Boxes and Diamonds. This is worth noting, because 1234D modalities are extremely common, probably because they are very easy to use; we literally use them on a day-to-day basis. Here is just a tiny selection of examples; you can substitute these ideas, or ideas like them, for the corners of the above diagram.

□ = ~◇~	~□~ = ◇	□~ = ~◇	~□ = ◇~
All	At Least Some	Not Even Some	Not All
Necessary	Possible	Impossible	Possibly Not
Always	Sometimes	Never	Not Always
Everywhere	Somewhere	Nowhere	Not Everywhere
Everybody	Somebody	Nobody	Not Everybody
Known	Not Ruled Out	Ruled Out	Not Known
Obligatory	Permissible	Impermissible	Omissible
Good	Acceptable	Unacceptably Bad	Bad Even If Tolerable
Great	At Least OK	Not Even OK	Not Great
Wholly	At Least Partly	Wholly Not	Not Wholly
Begins to Be	Does Not Begin Not to Be	Begins Not to Be	Does Not Begin to Be

Working out a square of opposition, even if you don't actually draw the diagram, is one of the most basic forms of analysis in modal reasoning, and it captures a significant portion of our day-to-day thought.

But 1234D modalities are not the end of the road, by any means; there are many more things yet to be done in order to understand how modal reasoning works. And we can start down that road by going back to our tables. We've been using a Reference Table to track what happens on the other tables. But we can actually do this in more than one way, and if we change the way we do things, we get something new.

Part VII

A Poem Draft

Pens

A little tube of ink -- a simple thing,
a pipe with viscous fluid flowing through,
mechanical device of purest kind,
no hope, no fear, or thought, or concern or care,
like water all still, unmoving and calm,
it strives not for greater nor higher, nor can.
Yet grasp the pen, and take it in your hand,
set it to paper, at an angle held,
and by it you may write a poem wise,
thought turned to symbol in deep black and white,
beyond what a pen by its own work may make,
beyond what it by its own means may mean.
As the water by moon will rise and fall
in grip of action of a higher force,
the pen taken in hand will fall and rise,
and, beyond its own power, shall words write.
So too you and I, by a sevenfold grace,
though human shall do the labors of God,
though limited, shall be infinite things,
though foolish, shall express divinest thoughts,
move like the sea with the force of the tide,
the pens of God writing heavenly truth.

The Hidden Treasure of the Interior Castle (Re-Post)

This is an old post that I am re-posting given the fortnightly book.

Saint Teresa of Avila has an important discussion of the soul and self-knowledge in her work, The Interior Castle (which can be found on-line here), a spiritual classic written in 1577 or shortly before. There she pictures the soul as a castle made of diamond or crystal, in which there are many rooms (aposentos), "just as in Heaven there are many mansions" (moradas) (1.1.1). The 'rooms' of this castle are connected with self-knowledge, for Teresa immediately goes on to say:

It is no small pity, and should cause us no little shame, that, through our own fault, we do not understand ourselves, or know who we are. Would it not be a sign of great ignorance, my daughters, if a person were asked who he was, and could not say, and had no idea who his father or his mother was, or from what country he came? Though that is great stupidity, our own is incomparably greater if we make no attempt to discover what we are, and only know that we are living in these bodies, and have a vague idea, because we have heard it and because our Faith tells us so, that we possess souls. As to what good qualities there may be in our souls, or Who dwells within them, or how precious they are -- those are things which we seldom consider and so we trouble little about carefully preserving the soul's beauty. All our interest is centered in the rough setting of the diamond, and in the outer wall of the castle -- that is to say, in these bodies of ours. (1.1.2)

So the idea is this: The soul is the castle itself; but the soul also in a sense occupies different rooms of itself through its knowledge of itself. As she notes, linking the issue of self-knowledge with prayer,

But you must understand that there are many ways of "being" in a place. Many souls remain in the outer court of the castle, which is the place occupied by the guards; they are not interested in entering it, and have no idea what there is in that wonderful place, or who dwells in it, or even how many rooms it has. You will have read certain books on prayer which advise the soul to enter within itself: and that is exactly what this means. (1.1.5)

Most of our self-knowledge is purely superficial - the outer wall of the castle, i.e., our body. Teresa is very insistent that there are many, many, many rooms in the castle; but the rooms also fall into rough groupings that can be distinguished according to interiority. The innermost room of the castle is the room "where the most secret things pass between God and the soul" (1.1.3). The Interior Castle is a guide to moving, through prayer, from the sort of self-knowledge we have in the outer part of the castle, to the sort we have in the inner part of the castle. (She divides the groupings into seven; of these we cannot get much farther than the second on our own - beyond that we need humility, prayer, and considerable reflection and meditation.) One of the interesting aspects of this whole picture is that Teresa was not the last to make use of it. Edith Stein uses it in Finite and Eternal Being. Edith Stein (1891-1942), for those who don't know, was a student of the philosopher Husserl. Jewish by background, she eventually converted to Catholicism and entered the Benedictine Order as a Carmelite. In 1942 the Nazis arrested her and sent her to Auschwitz-Birkenau, where she died. She was canonized in 1998, and so is known variously as "Saint Edith Stein" or "Saint Teresa Benedicta a Cruce," which was the name she took in honor of Teresa of Avila. The interior castle is introduced in part VII, section 3. There she notes (quotations are from Finite and Eternal Being, Kurt Reinhardt, tr., ICS Publications, Washington D. C., 2002):

The soul as the interior castle--as it was pictured by our holy mother Teresa--is not point-like as is the pure ego, but "spatial." It is a space, a "castle" with many mansions in which the I is able to move freely, now going outward beyond itself, now withdrawing into its own inwardness. And this space is not "empty," even though it can and must receive and harbor a fullness in order to become capable of unfolding its own individual life. (p. 373)

The soul 'dwells' in various aspects of itself: in the body, as sentient; in the spirit, as extending outside itself to recognize a world of persons, events, and things; and in "the personal I" or "pure ego". Stein is careful to indicate the point at which she is going beyond Teresa, saying, "St. Teresa was not interested in the question of whether the structure of the soul, aside from being the abode of God, has an independent meaning of its own and whether there is perhaps another entrance 'portal' to the soul's inwardness besides contemplative prayer" (p. 598 n. 33). In Stein's understanding of the interior castle, the dwelling-places are a significant fact about the very nature of the soul's 'inwardness' or self-consciousness; and the other entranceway is what she calls the "awake and conscious ego-life" (p. 375). It plays an important role in her attempt to clarify what it is to be a person. We have a genuine sort of soul-structure, a multifacetedness, in our self-knowledge; spatial metaphors are an attempt to characterize this, given that we don't have more convenient words for what is being discussed. She agrees with Teresa that the "ego which apprehends, observes, and works upon its own self as if this self were a purely external thing evidently does not have its seat in the interior of the castle" (p. 433), and that self-knowledge is closely related to interiority. As she says:

In its innermost being the essence of the soul is completely overt to itself. When the ego lives in this interiority, i.e., in the ground of its being where it is truly at home and in its own, it experiences in some measure the meaning of its being and feels the collected power that precedes the division into individual powers or faculties. And when the ego's life issues from this interiority, it lives a full life and attains to the height of its being. (p. 438)

This transformation to interiority is a gradual process; in particular, it is a gradual process in which the person becomes more fully what they are called to be: the call to interiority is an appeal to the person, to the intellect, to the free will. And we do experience a call to interiority. It does not compel, but to dwell in our castle in a more interior way is to understand ourselves more fully and to be more at home with who we are; the call to interiority is the call to 'take a stand' with respect to what sort of persons we will be, the voice of conscience: "Reason and faith are both appeals of the soul, calling it 'to enter into its own self' and to mold human life from the innermost center" (p. 440).

This only barely scratches the surface of the investigations of the two Teresas on this point. I find it immensely interesting from a philosophical perspective; in part, because I think they are both on to something very important about the nature of self-knowledge, and in part because it highlights that there is an immense amount of moral psychology and philosophical anthropology locked in spiritual classics. It's perhaps worth noting, too, that recognition of this is important to doing more justice to the actual participation of women in the Colloquium of Ages that is the history of philosophy. There are many important philosophical insights from women located in works of piety and spirituality with which, for various reasons, they often were in more of a position to write than they were to write any treatise that would be more stereotypically 'philosophical'.