Mind and Matter

In Book III of On the Soul, Aristotle argues that the intellect does not have a bodily organ:

Therefore, since everything is a possible object of thought, mind in order, as Anaxagoras says, to dominate, that is, to know, must be pure from all admixture; for the co-presence of what is alien to its nature is a hindrance and a block: it follows that it too, like the sensitive part, can have no nature of its own, other than that of having a certain capacity. Thus that in the soul which is called mind (by mind I mean that whereby the soul thinks and judges) is, before it thinks, not actually any real thing. For this reason it cannot reasonably be regarded as blended with the body: if so, it would acquire some quality, e.g. warmth or cold, or even have an organ like the sensitive faculty: as it is, it has none. It was a good idea to call the soul ‘the place of forms’, though (1) this description holds only of the intellective soul, and (2) even this is the forms only potentially, not actually.
Observation of the sense-organs and their employment reveals a distinction between the impassibility of the sensitive and that of the intellective faculty. After strong stimulation of a sense we are less able to exercise it than before, as e.g. in the case of a loud sound we cannot hear easily immediately after, or in the case of a bright colour or a powerful odour we cannot see or smell, but in the case of mind thought about an object that is highly intelligible renders it more and not less able afterwards to think objects that are less intelligible: the reason is that while the faculty of sensation is dependent upon the body, mind is separable from it.

There are two arguments here, one from the fact that the mind can understand at all, and the other from the effect of thinking about highly intelligible things.

St. Thomas explains the first argument:

The following argument may make this point clear. Anything that is in potency with respect to an object, and able to receive it into itself, is, as such, without that object; thus the pupil of the eye, being potential to colours and able to receive them, is itself colourless. But our intellect is so related to the objects it understands that it is in potency with respect to them, and capable of being affected by them (as sense is related to sensible objects). Therefore it must itself lack all those things which of its nature it understands. Since then it naturally understands all sensible and bodily things, it must be lacking in every bodily nature; just as the sense of sight, being able to know colour, lacks all colour. If sight itself had any particular colour, this colour would prevent it from seeing other colours, just as the tongue of a feverish man, being coated with a bitter moisture, cannot taste anything sweet. In the same way then, if the intellect were restricted to any particular nature, this connatural restriction would prevent it from knowing other natures. Hence he says: ‘What appeared inwardly would prevent and impede’ (its knowledge of) ‘what was without’; i.e. it would get in the way of the intellect, and veil it so to say, and prevent it from inspecting other things. He calls ‘the inwardly appearing’ whatever might be supposed to be intrinsic and co-natural to the intellect and which, so long as it ‘appeared’ therein would necessarily prevent the understanding of anything else; rather as we might say that the bitter moisture was an ‘inwardly appearing’ factor in a fevered tongue.

This is similar to St. Thomas’s suggestion elsewhere that matter and understanding are intrinsically opposed to one another. I cautioned the reader there about taking such an argument as definitive too quickly, and I would do the same here. Consider the argument about sensation: it is true enough that the pupil isn’t colored, and that perception of temperature is relative to the temperature of the organ of touch, or some aspects of it, which suggests that heat in the organ impedes the sensation of heat. On the other hand, the optic nerve and the visual cortex are arguably even more necessary to the sense of sight than the pupil, and they most certainly are not colorless. Taking this into consideration, the facts about the pupil, and the way touch functions, and so on, seem like facts that should be taken into consideration, but do not even come to close to establishing as a fact that the intellect does not have an organ.

Likewise, with the second argument, Aristotle is certainly pointing to a difference between the intellect and the senses, even if this argument might need qualification, since one does tire even of thinking. But saying that the intellect is not merely another sense is one thing, and saying that it does not have an organ at all is another.

We previously considered Sean Collins’s discussion Aristotle and the history of science. Following on one of the passages quoted in the linked post, Collins continues:

I said above that Aristotle thinks somewhat Platonically “despite himself.” He himself is very remarkably aware that matter will make a difference in the account of things, even if the extent of the difference remains as yet unknown. And Aristotle makes, in this connection, a distinction which is well known to the scholastic tradition, but not equally well understood: that, namely, between the “logical” consideration of a question, and the “physical” consideration of it. Why make that distinction? Its basis lies in the discovery that matter is a genuine principle. For, on the one hand, the mind and its act are immaterial; but the things to be known in the physical world are material. It becomes necessary, therefore, for the mind to “go out of itself,” as it were, in the effort to know things. This is precisely what gives rise to what is called the “order of concretion.”

But how much “going out of itself” will be necessary, or precisely how that is to be done, is not something that can be known without experience — the experience, as it turns out, not merely of an individual but of an entire tradition of thought. Here I am speaking of history, and history has, indeed, everything to do with what I am talking about. Aristotle’s disciples are not always as perspicacious as their master was. Some of them suppose that they should follow the master blindly in the supposition that history has no significant bearing on the “disciplines.” That supposition amounts, at least implicitly, to a still deeper assumption: the assumption, namely, that the materiality of human nature, and of the cosmos, is not so significant as to warrant a suspicion that historical time is implicated in the material essence of things. Aristotle did not think of time as essentially historical in the sense I am speaking of here. The discovery that it was essentially historical was not yet attainable.

I would argue that Sean Collins should consider how similar considerations would apply to his remark that “the mind and its act are immaterial.” Perhaps we know in a general way that sensation is more immaterial than growth, but we do not think that sensation therefore does not involve an organ. How confident should one be that the mind does not use an organ based on such general considerations? Just as there is a difference between the “logical” consideration of time and motion and their “physical” consideration, so there might be a similar difference between two kinds of consideration of the mind.

Elsewhere, Collins criticizes a certain kind of criticism of science:

We do encounter the atomists, who argue to a certain complexity in material things. Most of our sophomore year’s natural science is taken up with them. But what do we do with them? The only atomists we read are the early ones, who are only just beginning to discover evidence for atoms. The evidence they possess for atoms is still weak enough so that we often think we can take refuge in general statements about the hypothetical nature of modern science. In other words, without much consideration, we are tempted to write modern science off, so that we can get back to this thing we call philosophy.

Some may find that description a little stark, but at any rate, right here at the start, I want to note parenthetically that such a dismissal would be far less likely if we did not often confuse experimental science with the most common philosophical account of contemporary science. That most common philosophical account is based largely on the very early and incomplete developments of science, along with an offshoot of Humean philosophy which came into vogue mainly through Ernst Mach. But if we look at contemporary science as it really is today, and take care to set aside accidental associations it has with various dubious philosophies, we find a completely wonderful and astonishing growth of understanding of the physical structure not only of material substances, but of the entire cosmos. And so while some of us discuss at the lunch table whether the hypothesis of atoms is viable, physicists and engineers around the world make nanotubes and other lovely little structures, even machines, out of actual atoms of various elements such as carbon.

And likewise during such discussions, neuroscientists discuss which parts of the brain are responsible for abstract thought.

When we discussed the mixing of wine and water, we noted how many difficulties could arise when you consider a process in detail, which you might not notice simply with a general consideration. The same thing will certainly happen in the consideration of how the mind works. For example, how am I choosing these words as I type? I do not have the time to consider a vast list of alternatives for each word, even though there would frequently be several possibilities, and sometimes I do think of more than one. Other times I go back and change a word or two, or more. But most of the words are coming to me as though by magic, without any conscious thought. Where is this coming from?

The selection of these words is almost certainly being done by a part of my brain. A sign of this is that those with transcortical motor aphasia have great difficulty selecting words, but do not have a problem with understanding.

This is only one small element of a vast interconnected process which is involved in understanding, thinking, and speaking. And precisely because there is a very complex process here which is not completely understood, the statement, “well, these elements are organic, but there is also some non-organic element involved,” cannot be proved to be false in a scientific manner, at least at this time. But it also cannot be proved to be true, and if it did turn out to be true, there would have to be concrete relationships between that element and all the other elements. What would be the contribution of the immaterial element? What would happen if it were lacking, or if that question does not make sense, because it cannot be lacking, why can it not be lacking?

 

Mixing Water and Wine

St. Thomas discusses what happens if you mix consecrated wine with another liquid:

I answer that, The truth of this question is evident from what has been said already. For it was said above (3; 5, ad 2) that the species remaining in this sacrament, as they acquire the manner of being of substance in virtue of the consecration, so likewise do they obtain the mode of acting and of being acted upon, so that they can do or receive whatever their substance could do or receive, were it there present. But it is evident that if the substance of wine were there present, then some other liquid could be mingled with it.

Nevertheless there would be a different effect of such mixing both according to the form and according to the quantity of the liquid. For if sufficient liquid were mixed so as to spread itself all through the wine, then the whole would be a mixed substance. Now what is made up of things mixed is neither of them, but each passes into a third resulting from both: hence it would result that the former wine would remain no longer. But if the liquid added were of another species, for instance, if water were mixed, the species of the wine would be dissolved, and there would be a liquid of another species. But if liquid of the same species were added, of instance, wine with wine, the same species would remain, but the wine would not be the same numerically, as the diversity of the accidents shows: for instance, if one wine were white and the other red.

But if the liquid added were of such minute quantity that it could not permeate the whole, the entire wine would not be mixed, but only part of it, which would not remain the same numerically owing to the blending of extraneous matter: still it would remain the same specifically, not only if a little liquid of the same species were mixed with it, but even if it were of another species, since a drop of water blended with much wine passes into the species of wine (De Gener. i).

Now it is evident that the body and blood of Christ abide in this sacrament so long as the species remain numerically the same, as stated above (4; 76, 6, ad 3); because it is this bread and this wine which is consecrated. Hence, if the liquid of any kind whatsoever added be so much in quantity as to permeate the whole of the consecrated wine, and be mixed with it throughout, the result would be something numerically distinct, and the blood of Christ will remain there no longer. But if the quantity of the liquid added be so slight as not to permeate throughout, but to reach only a part of the species, Christ’s blood will cease to be under that part of the consecrated wine, yet will remain under the rest.

Given the doctrine of transubstantiation, at least as St. Thomas understands it, so that it implies the existence of accidents without a subject, it is very difficult to understand how such a mixing would be possible at all. But his general position here is that a process analogous to substantial change necessarily happens if you mix anything into the consecrated wine, either according to a part of the wine, or according to the whole. He explains this kind of change in article five of the same question:

I answer that, Since “the corruption of one thing is the generation of another” (De Gener. i), something must be generated necessarily from the sacramental species if they be corrupted, as stated above (Article 4); for they are not corrupted in such a way that they disappear altogether, as if reduced to nothing; on the contrary, something sensible manifestly succeeds to them.

Nevertheless, it is difficult to see how anything can be generated from them. For it is quite evident that nothing is generated out of the body and blood of Christ which are truly there, because these are incorruptible. But if the substance, or even the matter, of the bread and wine were to remain in this sacrament, then, as some have maintained, it would be easy to account for this sensible object which succeeds to them. But that supposition is false, as was stated above (75, 2,4,8).

Hence it is that others have said that the things generated have not sprung from the sacramental species, but from the surrounding atmosphere. But this can be shown in many ways to be impossible. In the first place, because when a thing is generated from another, the latter at first appears changed and corrupted; whereas no alteration or corruption appeared previously in the adjacent atmosphere; hence the worms or ashes are not generated therefrom. Secondly, because the nature of the atmosphere is not such as to permit of such things being generated by such alterations. Thirdly, because it is possible for many consecrated hosts to be burned or putrefied; nor would it be possible for an earthen body, large enough to be generated from the atmosphere, unless a great and, in fact, exceedingly sensible condensation of the atmosphere took place. Fourthly, because the same thing can happen to the solid bodies surrounding them, such as iron or stone, which remain entire after the generation of the aforesaid things. Hence this opinion cannot stand, because it is opposed to what is manifest to our senses.

And therefore others have said that the substance of the bread and wine returns during the corruption of the species, and so from the returning substance of the bread and wine, ashes or worms or something of the kind are generated. But this explanation seems an impossible one. First of all, because if the substance of the bread and wine be converted into the body and blood of Christ, as was shown above (75, 2,4), the substance of the bread and wine cannot return, except the body and blood of Christ be again changed back into the substance of bread and wine, which is impossible: thus if air be turned into fire, the air cannot return without the fire being again changed into air. But if the substance of bread or wine be annihilated, it cannot return again, because what lapses into nothing does not return numerically the same. Unless perchance it be said that the said substance returns, because God creates anew another new substance to replace the first. Secondly, this seems to be impossible, because no time can be assigned when the substance of the bread returns. For, from what was said above (4; 76, 6, ad 3), it is evident that while the species of the bread and wine remain, there remain also the body and blood of Christ, which are not present together with the substance of the bread and wine in this sacrament, according to what was stated above (Question 75, Article 2). Hence the substance of the bread and wine cannot return while the sacramental species remain; nor, again, when these species pass away; because then the substance of the bread and wine would be without their proper accidents, which is impossible. Unless perchance it be said that in the last instant of the corruption of the species there returns (not, indeed, the substance of bread and wine, because it is in that very instant that they have the being of the substance generated from the species, but) the matter of the bread and wine; which, matter, properly speaking, would be more correctly described as created anew, than as returning. And in this sense the aforesaid position might be held.

However, since it does not seem reasonable to say that anything takes place miraculously in this sacrament, except in virtue of the consecration itself, which does not imply either creation or return of matter, it seems better to say that in the actual consecration it is miraculously bestowed on the dimensive quantity of the bread and wine to be the subject of subsequent forms. Now this is proper to matter; and therefore as a consequence everything which goes with matter is bestowed on dimensive quantity; and therefore everything which could be generated from the matter of bread or wine, if it were present, can be generated from the aforesaid dimensive quantity of the bread or wine, not, indeed, by a new miracle, but by virtue of the miracle which has already taken place.

This is rather strange, because he seems to be saying that the subsequent substantial forms inhere in quantity as in a subject, and that there is no matter there. But if this is possible in any way, and in particular if things remain in this state permanently, as he seems to suggest, then there seems to be little reason not to adopt Descartes’s view of material substance in general, and say that quantity is always the subject of substantial forms, rather than saying that some parts of the world have matter as a subject, and other parts quantity. The account might be more reasonable if he were to accept that when a new substance is generated, matter again comes to be, not by being “created anew,” but because the being of matter in general is from substantial form.

As we can see, this discussion is especially complex on account of the doctrine of transubstantiation and St. Thomas’s account of that doctrine. But if we simply consider the mixing of two liquids in general, various difficulties will remain. Suppose we have a glass of water and a glass of wine, and mix the two together. What exactly will happen?

It is manifest to the senses that when we do this, there is a period of time when parts of the resulting liquid are water, just as it was, and parts are wine, just as it was, without any mixture. But what about the surface where the two are in contact? What is happening there?

According to St. Thomas, there will be a quantitative part which shares in the qualities of each. And this is pretty reasonable. Just as we can see that part is wine and part is water, at a certain point we can see that part is watery wine. But how exactly did that watery part get that way? If it is a certain size, was there a sudden transition of a part which was water into the watery wine? Or the like with the wine becoming watery? Or was there a continuous process with an expanding mixed region? The last possibility seems most consistent with what we see, but it might be difficult to analyze this in terms of substantial change, as St. Thomas does, because such a continuous process would have no first moment when the mixed substance came to be. For if it did, it would come to be with a definite size, and thus the process would not be continuous, but would imply that some part suddenly went from not being watery wine to being watery wine.

Of course, it is one thing to say there are difficulties. It is quite another to say that they mean that the thing cannot happen. So none of this proves that the mixing of liquids is not a substantial change. Nonetheless, many of the ancient naturalists were moved by such considerations to adopt some form of atomic theory. If water and wine are each composed of atoms, the mixing process is easily understood — it is simply the movement in place of these atoms. Each part of the water remains as it was even qualitatively, and likewise each part of the wine, but the resulting mixture has different sensible qualities because one cannot distinguish the diverse qualities of each, just as mixing two very fine sands of different color may appear to result in a third color, even though the grains of sand are not changing qualitatively.

Modern atomic theory, of course, has far stronger arguments for it, but they are in principle, or at least were in the 18th and 19th centuries, of a very similar kind: atomic theory simply does a good job of explaining many of the things that we see happen in the world.

This is closely related to the discussion in the last post. When we construct a bicycle out of parts, it is manifest to the senses that the parts look just like they did before they were parts. And this is necessary, if it is true that those parts are governed by the same natural laws after they become parts that they were before they became parts. For however the parts “look,” they look this way because of how they act on the senses. So if their action does not change, the “way they look” will not change. Similarly, when we mix liquids, if the water parts and the wine parts do not change how they behave, the account one gives of the mixture must be an atomic theory or something very like it. That is, there must remain very small parts that act like water, and very small parts that act like wine. Or, given that wine and water are not in fact elements, at least the basic elemental parts must continue to act like those elemental parts.