Contrary to the postulations of some spiritualistic philosophies, the intuition of consciousness does not disclose, without further ado, the nature of our acts, of our powers, and of our substance. Consciousness tells me that I think, that I will, that I freely choose, and that I am. But in order to know what thought is, what the will is, what freedom is; in order to know whether I am a substance or a bundle of phenomena, a piece of extension or a spirit, or a composite of body and spirit, awareness of my activities does not suffice. It is necessary to subject these activities to analysis, to disengage their forms from surrounding contingencies, to compare, to judge and to reason; in a word, to exercise science and philosophy. No intuition can be substituted for the work of the reason and dispense with its difficulties: this holds for the soul as well as for nature. It is up to the spontaneous philosophy of common sense, and later to the technically worked-out philosophy of the philosophers to render explicit and distinct what immediate experience presents in confusion.
Yves R. Simon, Freedom of the Will. Peter Wolff, tr. & ed. Fordham University Press (New York: 1969) pp. 81-83.
A big philosophical amen to that. It's really quite surprising how commonly philosophical arguments presuppose that knowledge of one's own nature is easy; whereas in reality, beyond a certain elementary level, it is one of the most difficult topics of inquiry that can be proposed. This underestimation of how tricky it is to know oneself in a robust sense is a flaw that occurs all over the place, on every side of every question that appeals to facts about what we are.