Descartes then was inconsistent with his own principles when he made this jump to a new sphere of being. The sameness of the experienced object is ultimate; the only pertinent question is, what does it mean? It means, as I have said, that the wax hard and the wax soft are the same in sense third. But sameness in sense third admits of wide dissimilarities in the experiences it unites into the notion of the one object. Descartes looked for a sameness without these dissimilarities. He would reduce sense third to sense first, or, perhaps, to sense second. To do this he must go behind the experiences to a "real" thing, which is to remain the same as a proxy for what is evidently variable. This makeshift is only satisfactory to one who overlooks, or allows to fall into the background, the plain fact that representative and thing represented are two separate things and not to be confused; that is, who confuses sameness in sense first with sameness in sense seventh. Descartes distinguished carefully between ideas and external things, but he sometimes overlooked the distinction. "But what is this bit of wax that cannot be comprehended save by the understanding or the mind? It is certainly the same that I see, that I touch, that I imagine; it is, in a word, the same that I have always thought it from the beginning." How ambiguous! is it the same in sense first or sense seventh? The sentence following would indicate sense seventh, but the spirit of the whole discussion would argue for sense first. One must delude oneself into believing that one can get at "real" wax directly, in some way or other, or one cannot think of making it an ultimate ground of reasoning. Descartes, like so many others, would seem to have vibrated between a clear consciousness that ideas and "real" things are distinct, belonging to different worlds, and a confused belief that they belong to the one world, and that "real" things are open to direct observation.
I shall take still another extract from this author. It contains similar errors.
"Now, among these ideas, some appear to me to be inborn, others to be foreign and to come from without, and still others to be made and invented by myself. For, as to the faculty of conceiving that which, in general, one calls a thing, or a truth, or a thought, it appears to me that I do not get that from any other source than my own nature; but if now I hear a sound, if I see the sun, if I feel the heat, up to the present I have judged that these sensations proceed from things which exist without me; and lastly, it seems to me that syrens, hippogriffs, and all similar chimeras are fictions and inventions of my mind. But perhaps I can persuade myself, that all these ideas belong to the class of those that I call foreign, and that come to me from without, or that they are all innate, or else that they are all created by myself; for I have not yet clearly discovered their true source. And my chief duty here is to consider, touching those which seem to come from objects without me, what reasons I have for thinking them like their objects.
"The first of the reasons is that I seem to be taught to do so by nature; and the second, that I perceive that these ideas are not dependent upon my will; for often they present themselves to me in spite of me, as now, whether I wish it or not, I feel heat, and consequently am persuaded that this sensation or idea of heat is produced in me by something different from me, to wit: by the heat of the fire by which I am sitting. And I cannot see that anything is more reasonable than to judge that this external object emits and impresses upon me its resemblance rather than anything else.
"Now I must see if these reasons are sufficiently strong and convincing. When I say that I seem to be taught so by nature, I mean merely by this word nature a certain inclination which leads me to believe it, and not a natural light which gives me certain knowledge that it is true. But these two ways of speaking are very different, for I cannot doubt anything that the natural light shows me to be true, as it has just shown me that from the fact of my doubting I may infer my existence; inasmuch as I have not in me any other faculty or power of distinguishing the true from the false to teach me that what this light shows me to be true is not true, and in which I may have as much confidence as in it. But as concerns inclinations which also seem to me natural, I have often remarked, when it has been a question of choice between virtues and vices, that they do not less incline to evil than to good; it follows that I have no more reason to follow them when the true and the false are in question. And as for the other reason, which is that these ideas must come from without, since they are not dependent on my will, I do not find it more convincing. For while these inclinations of which I have just spoken are in me, notwithstanding that they are not always in harmony with my will, perhaps there is in me some faculty or power capable of producing these ideas without the aid of external things, although it is yet unknown to me; as indeed it has always seemed to me up to this time that when I sleep they are thus formed in me without the aid of the objects they represent. Finally, even should I admit that they are caused by these objects, it does not necessarily follow that they must be like them. On the contrary, I have often remarked in many instances, that there is a great difference between an object and its idea: as, for example, I find in me two very different ideas of the sun; the one has its source in the senses, and should be placed in the class of those which I have said above come from without, and from this it seems to me very small; the other has it origin in astronomical reasonings, that is to say, in certain notions which are inborn, or else formed in some way or other by myself, and from this it seems to me many times greater than the whole earth. Surely, these two ideas which I have of the sun cannot both be like the same sun; and reason convinces me that the one which is derived directly from its appearance is the one which is most unlike it. All of which proves to me that, up to this hour, it has not been by a sure and premeditated judgment, but merely by a blind and rash impulse, that I have been led to believe that there are things without me, and different from my being, which, by the organs of my senses, or by whatever other means, convey to me their ideas or images, and impress upon me their resemblances."[52]
From the earlier portions of this extract one may see how clearly Descartes distinguished between the idea, or the thing immediately known, and the external thing which he assumed as corresponding to the idea; from the latter part one may see how he sometimes confounded them. He finds that he may doubt whether ideas have any external correlatives; and, granting that they have, whether the two resemble each other at all. All this would imply that "external" things are completely cut off from observation. And yet he states with naïveté that he has "often remarked in many instances that there is a great difference between an object and its idea." Now, if this can really be remarked in many instances, the doubt as to the existence of objects would seem to be groundless. How can it be remarked? On this point Descartes is silent. He has evidently fallen back upon the popular notion that under favorable circumstances one can get a look at a "real" thing, just as it is. The "reason" which convinces him that the astronomer's notion of the sun is the true notion is nothing but this. It could certainly not be deduced from his only argument for the existence of external things—the veracity of God. How does he know, that in giving us several different ideas of the sun, God has chosen to have this one only resemble it? It is a pure assumption. Reason is of service when one has something to go upon; but in the absence of premises it will not carry one far. This assumption is an illustration of what I had occasion to remark upon in criticizing Pyrrho; of the fact that, from the series of possible perceptions which we group together as one object, we are apt to select one, to us for some reason the most satisfactory one, and to regard it as more truly representing the object than the others. Descartes has followed this impulse, and made this perception the best representative of the "real" object. Had he always distinguished sameness in sense first from sameness in sense seventh, he would have seen how purely gratuitous is his assumption.
The statement, too, that two different ideas of the sun cannot both resemble the same sun, shows how little he comprehended what it meant by the word same when used in the third sense. If by the sun we mean a whole series of possible perceptions, perhaps quite unlike each other, but all united and related in certain ways, there is nothing to prevent very dissimilar things from being like the same sun. Each of them need only resemble a single link in the series. By the words "the same sun" Descartes meant the same in sense first, but this sins against the proper meaning of the term. The difficulty is self-created.
Descartes' sun reminds me of Berkeley's moon. This latter writer clearly perceived that there may be multiplicity and diversity where one attributes sameness in sense third. Note the following:
"But for a fuller explication of this point, and to show that the immediate objects of sight are not so much as the ideas or resemblances of things placed at a distance, it is requisite that we look nearer into the matter, and carefully observe what is meant in common discourse when one says that which he sees is at a distance from him. Suppose, for example, that looking at the moon I should say it were fifty or sixty semidiameters of the earth distant from me. Let us see what moon this is spoken of. It is plain it cannot be the visible moon, or anything like the visible moon, or that I see—which is only a round, luminous plain, of about thirty visible points in diameter. For, in case I am carried from the place where I stand directly toward the moon, it is manifest the object varies still as I go on; and, by the time that I am advanced fifty or sixty semidiameters of the earth, I shall be so far from being near a small, round, luminous flat that I shall perceive nothing like it—this object having long since disappeared, and, if I would recover it, it must be by going back to the earth from whence I set out."[53]
So much for dissimilar experiences of the same object. And Berkeley is not impelled to assume an external something to explain how the object can be the same under the circumstances. The case, he finds, stands thus: