Descartes would, and indeed did, object to this. He informed others that if they were not able to conceive of God “clearly and distinctly,” they must “meditate” and eventually they will conceive of God, and if they do not, it is by their own flaw that they fail to conceive God. Yet, Descartes claimed that the concept of God (the infinite) must come from God, and not from man, because man is not infinite. And still he claims that it is man's responsibility to “meditate” and thereby conceive of God?
In this sense, Descartes would have to concede that understanding, like existence, can only be known, for sure, of oneself. And, one cannot convince others that they understand, nor can they be convinced that another understands.
Solipsism in Wittgenstein's theory of understanding is perhaps a bit more difficult to uncover, but as I am determined, I will try. Wittgenstein seeks to redefine the notion of understanding; he has a distaste for the notion of understanding as the occurrence of a mental image, and suggests that understanding is revealed in the performance of a task one was asked to perform. However, each task requires that one learn the “meanings” of words, or the use of words, in order to accomplish desired tasks. In the example noted in the text above, Wittgenstein recounts what teaching of this sort would look like. He explains a situation in which one is taught by means of conditioning, by the repetitive affiliation of an object, color, or action with a word.
Understanding, then, is exhibited when one performs, after their process of learning, a task that is asked of them, like the example Wittgenstein gives, “select the yellow ball from the bag.” In this instance, for Wittgenstein, understanding is the accomplishing of the task asked by the instructor. However, in a metaphysical sense, at least for Descartes, understanding seems to be something more than performing a task. Take an example. Imagine that I am kindergarten teacher and I ask my student, Tommy, to bring me the red ball; he fishes through the veritable spectrum of balls and picks up a blue ball and brings it to me. I say “no, that's blue, I asked for red, can you bring it to me, please?” And, again, he returns to the pile fishing through (at this point it is obviously clear that he does not know what the red ball is, because he has picked it up and put it back down several times), but by some stroke of luck, he this time picks up the red ball and brings it to me. I say, “Good job, Tommy, you have done what I told you.” Would I say, here, that Tommy has understood? Wittgenstein would say yes, but how am I to know that Tommy actually understood that he picked up the red ball, and that he didn't merely note that I affirmed him when he picked up the red ball, which could be cause enough for him to do it again. How do I know that he was not responding to my praise, but rather, he understood what I meant when I said, “Bring me the red ball?” Or, how do we know that it was not by luck that Tommy selected the red ball, and that he happens to be lucky enough to select it time after time? I do not believe we can know.
Wittgenstein may object to this, and he may claim that understanding arises in the use of language to communicate and elicit response. In this way, then, Wittgenstein has reduced understanding merely to performing the task that one has asked to perform. But, to define understanding in this way leaves out the skeptical criticisms noted above. Namely, that these acts may be occurring by the process of luck, or that one is merely responding to the affirmation of the one giving the order, and, seeking to again be praised, repeat their actions we asked to perform the same task. In this way, it seems as though Wittgenstein is also unable to evade the pitfall of solipsism. He has no way of knowing the underlying processes by which one performs the task asked of them, and until he is able to do that, it would have to be said that his is a solipsistic theory.
What, then, can we conclude of all of this. Well, appealing to the pragmatic response, it seems one would have to concede that describing understanding in an either/or way: either Descartes' or Wittgenstein's view, proves, in the end, to get one trapped at the same place of solipsism. This would also be true of hybridizing the views of these two philosophers, because neither "half" answers the solipsistic question that is the downfall of the other. So, it seems that there is one of two views one can adopt, pragmatically speaking. First, one can simply concede that whatever metaphysical view one holds of understanding, one will end up in the solipsistic trap, in a place without the hope of being able to prove to others one's own understanding, and a place without the hope of being able to prove to oneself the understanding of others. Secondly, and perhaps more favorably, one can embark on the hopeful journey of attempting a new metaphysical description of understanding. It is beyond the scope of this paper, and indeed beyond my ability to suggest what such a description might look like, but it is my invitation to philosophers more skilled than myself to help us overcome solipsism.
This is taken from the “Fourth Meditation,” but this also represents traces of previous conclusions Descartes had made in Meditations two and three (meditation two=Cogito argument, “I think, therefore I am.” and meditation three=the existence of God in a “clear and distinct” concept of the infinite).
The earlier part of this is found in both meditation three and four, “clear and distinct” occurs first in meditation three.
This is taken from p. 39 of “Fourth Meditation,” and this is the crux of Descartes' treatment of understanding. It is from here that one gets a picture of Descartes' view of understanding as being a product of faculties within a person: the faculty of intellect (perception) and the faculty of freedom (will).
This is taken from p. 41 of “Fourth Meditation,” and this sums up Descartes theory of error and “sin.” It also says a great deal about his view of understanding.
This is a direct quote taken from the “Blue and Brown Books.” It is in the midst of his explanation of understanding being revealed in action, not in imagination or a mental process.
This is also a direct quote from “Blue and Brown Books.” This is Wittgenstein's critique of the notion of a mental form of understanding.
