Multiple existences
Let us, then, explore our effect further, and see if there is anything more that must be true of the cause (i.e. of any explanation whatever) or the effect remains impossible.
Conclusion 1: There are many different existences.
The reason for this is the following: We know that our consciousness is just one consciousness, though it takes on many different forms. Now since different effects have different causes, it follows that if there are two different ways of being conscious, the causes must be different. But the difference can't come from the consciousness itself (which is one consciousness), nor from the mind (which is one mind, unifying it), and so it must come from existence. But if existence were absolutely the same in both cases, then there would be an absolutely identical total cause in both cases, and identical causes have identical effects. Therefore, the cause of our being conscious in different ways is that there are different existences.
So already we are one step beyond Kant, who held that there is some "x" "out there" which is responsible for the "manifold of sensation," but that we could say absolutely nothing about it because we could not know it as it is "in itself." True, we can't know it as it is in itself; but we can know what it has to be if it is going to make sense out of our consciousness; and one of the things it has to be is multiple or our consciousness as differentiated from itself (in many forms) is impossible.
So Jean-Paul Sartre's gimmick in Being and Nothingness won't work. His idea is that "being" is one undifferentiated blob, and I "nothingize" it into "chunks" of "beings"; the limits of each "being" of my experience come from me, by blocking it off into an object. But this won't wash. If I do the job, then since I am the same all the time, and if being is the same all the time, this "nothingizing" must not simply be non-rational, it is positively irrational. You have all these different effects (the different "beings" within my experience) due to identically the same cause; and since the theorems about causes and effects are simply tautologies from the Principle of Causality, which itself is a tautology from the Principle of Contradiction, then Sartre is violating the Principle of Contradiction in his theory. Now, of course, you could say that I, as "subject," and so "nothing," am different all the time; but then you have the problem of how all these different "subjects" get to be the same one that "answers to the same name" without any unifying thread. Instead of just going to sleep and waking up a different person, on this view as soon as you have a different experience the one who is having it would be different. No, there's no way you can make sense out of this; and Sartre himself says, of course, that if his theory is true, things are "absurd." If so, why write a book about it? It can't be true (and not false) that what is true is false.
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