I am, moreover, in exactly the same position when I adopt the exceptional point of view and think of my own thought-processes. I can never observe my present thought, I can only make my past experiences of thought-processes subsequently the objects of fresh thoughts. If I wanted to watch my present thought, I should have to split myself into two persons, one to think, the other to observe this thinking. But this is impossible. I can only accomplish it in two separate acts. The observed thought-processes are never those in which I am actually engaged but others. Whether, for this purpose, I make observations on my own former thoughts, or follow the thought-processes of another person, or finally, as in the example of the motions of the billiard balls, assume an imaginary thought-process, is immaterial.
There are two things which are incompatible with one another: productive activity and the theoretical contemplation of that activity. This is recognised even in the First Book of Moses. It represents God as creating the world in the first six days, and only after its completion is any contemplation of the world possible: “And God saw everything that he had made and, behold, it was very good.” The same applies to our thinking. It must be there first, if we would observe it.
The reason why it is impossible to observe the thought-process in its actual occurrence at any given moment, is the same as that which makes it possible for us to know it more immediately and more intimately than any other process in the world. Just because it is our own creation do we know the characteristic features of its course, the manner in which the process, in detail, takes place. What in the other spheres of observation we can discover only indirectly, viz., the relevant objective nexus and the relations of the individual objects, that is known to us immediately in the case of thought. I do not know off-hand why, for perception, thunder follows lightning, but I know immediately, from the content of the two concepts, why my thought connects the concept of thunder with that of lightning. It does not matter for my argument whether my concepts of thunder and lightning are correct. The connection between the concepts I have is clear to me, and that through the very concepts themselves.
This transparent clearness in the observation of our thought-processes is quite independent of our knowledge of the physiological basis of thought. I am speaking here of thought in the sense in which it is the object of our observation of our own mental activity. For this purpose it is quite irrelevant how one material process in my brain causes or influences another, whilst I am carrying on a process of thought. What I observe, in studying a thought-process, is, not what process in my brain connects the concept of thunder with that of lightning, but what is my reason for bringing these two concepts into a definite relation. Introspection shows that, in linking thought with thought, I am guided by their content, not by the material processes in the brain. This remark would be quite superfluous in a less materialistic age than ours. To-day, however, when there are people who believe that, when we know what matter is, we shall know also how it thinks, it is necessary to affirm the possibility of speaking of thought without trespassing on the domain of brain physiology. Many people to-day find it difficult to grasp the concept of thought in its purity. Anyone who challenges the account of thought which I have given here, by quoting Cabanis’ statement that “the brain secretes thoughts as the liver does gall or the spittle-glands spittle, etc.” simply does not know of what I am talking. He attempts to discover thought by the same method of mere observation which we apply to the other objects that make up the world. But he cannot find it in this way, because, as I have shown, it eludes just this ordinary observation. Whoever cannot transcend Materialism lacks the ability to throw himself into the exceptional attitude I have described, in which he becomes conscious of what in all other mental activity remains unconscious. It is as useless to discuss thought with one who is not willing to adopt this attitude, as it would be to discuss colour with a blind man. Let him not imagine, however, that we regard physiological processes as thought. He fails to explain thought, because he is not even aware that it is there.
For every one, however, who has the ability to observe thought, and with good will every normal man has this ability, this observation is the most important he can make. For he observes something which he himself produces. He is not confronted by what is to begin with a strange object, but by his own activity. He knows how that which he observes has come to be. He perceives clearly its connections and relations. He gains a firm point from which he can, with well-founded hopes, seek an explanation of the other phenomena of the world.
The feeling that he had found such a firm foundation, induced the father of modern philosophy, Descartes, to base the whole of human knowledge on the principle, “I think, therefore I am.” All other things, all other processes, are independent of me. Whether they be truth, or illusion, or dream, I know not. There is only one thing of which I am absolutely certain, for I myself am the author of its indubitable existence; and that is my thought. Whatever other origin it may have in addition, whether it come from God or from elsewhere, of one thing I am sure, that it exists in the sense that I myself produce it. Descartes had, to begin with, no justification for reading any other meaning into his principle. All he had a right to assert was that, in apprehending myself as thinking, I apprehend myself, within the world-system, in that activity which is most uniquely characteristic of me. What the added words “therefore I am” are intended to mean has been much debated. They can have a meaning on one condition only. The simplest assertion I can make of a thing is, that it is, that it exists. What kind of existence, in detail, it has, can in no case be determined on the spot, as soon as the thing enters within the horizon of my experience. Each object must be studied in its relations to others, before we can determine the sense in which we can speak of its existence. An experienced process may be a complex of percepts, or it may be a dream, an hallucination, etc. In short, I cannot say in what sense it exists. I can never read off the kind of existence from the process itself, for I can discover it only when I consider the process in its relation to other things. But this, again, yields me no knowledge beyond just its relation to other things. My inquiry touches firm ground only when I find an object, the reason of the existence of which I can gather from itself. Such an object I am myself in so far as I think, for I qualify my existence by the determinate and self-contained content of my thought-activity. From here I can go on to ask whether other things exist in the same or in some other sense.
When thought is made an object of observation, something which usually escapes our attention is added to the other observed contents of the world. But the usual manner of observation, such as is employed also for other objects, is in no way altered. We add to the number of objects of observation, but not to the number of methods. When we are observing other things, there enters among the world-processes—among which I now include observation—one process which is overlooked. There is present something different from every other kind of process, something which is not taken into account. But when I make an object of my own thinking, there is no such neglected element present. For what lurks now in the background is just thought itself over again. The object of observation is qualitatively identical with the activity directed upon it. This is another characteristic feature of thought-processes. When we make them objects of observation, we are not compelled to do so with the help of something qualitatively different, but can remain within the realm of thought.
When I weave a tissue of thoughts round an independently given object, I transcend my observation, and the question then arises, What right have I to do this? Why do I not passively let the object impress itself on me? How is it possible for my thought to be relevantly related to the object? These are questions which every one must put to himself who reflects on his own thought-processes. But all these questions lapse when we think about thought itself. We then add nothing to our thought that is foreign to it, and therefore have no need to justify any such addition.
Schelling says: “To know Nature means to create Nature.” If we take these words of the daring philosopher of Nature literally, we shall have to renounce for ever all hope of gaining knowledge of Nature. For Nature after all exists, and if we have to create it over again, we must know the principles according to which it has originated in the first instance. We should have to borrow from Nature as it exists the conditions of existence for the Nature which we are about to create. But this borrowing, which would have to precede the creating, would be a knowing of Nature, and would be this even if after the borrowing no creation at all were attempted. The only kind of Nature which it would be possible to create without previous knowledge, would be a Nature different from the existing one.
What is impossible with Nature, viz., creation prior to knowledge, that we accomplish in the act of thought. Were we to refrain from thinking until we had first gained knowledge of it, we should never think at all. We must resolutely think straight ahead, and then afterwards by introspective analysis gain knowledge of our own processes. Thus we ourselves create the thought-processes which we then make objects of observation. The existence of all other objects is provided for us without any activity on our part.