Let us first contemplate the action of the primary intellectual faculties—Sense, or the faculty of external perception; Consciousness, the faculty of internal observation; and Reason, the faculty which gives us necessary and universal truths. The two former faculties give us phenomena external and internal. The latter gives us the logical antecedents of phenomena, thus perceived and affirmed, to wit: the ideas of substance, cause, space, time, &c. In the action of these faculties, surely, real error is impossible.