The third part of human consciousness, the body--its organic laws, powers, and properties, the philosopher must leave to the naturalist. It is only when it has reference to the higher parts of consciousness that its properties can be made the matter of his investigation. The soul and the mind form the fit and peculiar subject of his enquiries. To the mind belong the faculties of will and understanding--to the soul, those of reason and imagination. Schlegel observes it is remarkable that the three different species of mental alienation correspond to the three parts of human consciousness. Thus monomania springs from some error deeply rooted in the mind--frenzy is the disorder of a soul that has broken loose from all the restraints of reason; and idiotcy arises from some organic defect in the brain. The last is the effect of physical, the two former the consequence of moral, and frequently accidental, causes. The author lays it down as a general principle, subject, however, to many modifications and exceptions, that in man mind or thought predominates--in woman soul or feeling prevails. Hence in marriage, which is a sacred union of souls, the deficiencies in the psychology of either sex are happily and mutually supplied. On this subject, Schlegel has some of the most touching and beautiful reflections, which a loving heart and a noble fancy have ever inspired. Imagination (Einbildungs-kraft) is the inventive faculty--Reason (Vernunft) the regulative--Understanding (Verstand) the penetrative, or in a higher degree the intuitive--and the Will (Wille) the moral, faculty. To these primary faculties, or as the author styles them, these main boughs of human consciousness, four secondary faculties are subservient--the memory--the conscience--the passions or natural impulses, and the outward senses. The memory is the intermediate faculty between the understanding and the reason--the conscience the intermediate faculty between the reason and the will--the passions or natural impulses the intermediate faculty between the will and the imagination--and the outward senses form the connecting link between the imagination and the body. Reason is the regulative faculty implanted in the soul. In real life, it corresponds to what we commonly call judgment, and is that faculty by which the transactions of men are regulated, and the resolutions of the will are brought to maturity, whether in sacred or secular concerns. In science, Reason is the dialectical or analytic faculty, by which the discoveries of Imagination and the perceptions of the Understanding receive a definite form--the faculty of analysis, arrangement, and combination. Reason in itself is not inventive--it makes no discoveries--it is rather a negative than a positive faculty--but it is the indispensable arbitress, to whose decision Understanding and Imagination must submit their various productions.