We know that the self exists. But what is its nature? Here again, we run across a theory that we've already examined from another perspective. We want to ask if, as some philosophers claim, there's something in us besides the self, something distinct from the body – if somehow the inner world transcends that revealed to us by consciousness – if, in short, the soul is greater than the self.

Maine de Biran believed that it is, pointing to another reality beneath the self that serves as a substratum of conscious reality. By contrast with the active self, he gave the name “substance” to this other part of us. Cousin also believed there's something outside the self that escapes consciousness, whose existence is implied by reason alone.

But what we said about Hartmann and the Philosophy of the Unconscious refutes this theory. Quite aside from the fact that there aren't any unconscious psychic facts, the concept of substance is vague, empty, and indeterminate. What's the nature of this unconscious being? By definition, it's not active, and if it were, it would give rise to phenomena that would be observable by consciousness. Since it's inactive, all it can do is serve as the foundation for the self's actions. The only role that Maine de Biran gives this unconscious being is to serve in support of the self. But as we can't even imagine such a being, the concept of substance is void of any precise meaning.