It is painful to reflect on their former treatment; caged in iron-gratings and exhibited for money! Treated as wild beasts, they necessarily became like them, or worse! Devils in revenge and evil, Satans in deceit and delusion! Or if any portion of the man remained, think of the spirit writhing in agony, or sinking with despair within them! All this, and worse, in some despotic countries, even now exists; and in how many places are they not still made to drink the bitter cup of neglect and coldness, contempt and cruelty. Where do they receive, as they ought, judiciously and constantly, the cordial of sympathy and friendship? Where is every appearance of confinement and injurious association carefully avoided, and every thing studied to make them feel at home, and all this combined with medical attendance? Say not all this is unnecessary; for if life, under any circumstances, cannot be said to exist without some association of sympathy, it is certain there are among the insane, cases of misery and wretchedness which absolutely require for their cure, as well as their comfort, all the moral kindness and medical attention we can possibly give them. It has been an universal complaint, that there is nothing certain or fixed in the treatment of Insanity, and that it is presumed it is not yet fully understood. I am of opinion that no medical treatment in any case can be fixed as certain or judicious unless we understood the origin and nature of disease; and I have therefore devoted a considerable portion of this Essay to the consideration of the correspondence which exists between the causes and effects produced; and this I only consider as preliminary to a more full and adequate investigation of causes than I am aware has hitherto been made; but still, as preliminary to this important subject, I shall, in my next Essay, first give a general explanation of the origin and cause of disease, and this in agreement with a principle which I conceive to be of universal application. APPENDIX TO THE ESSAY ON CLASSIFICATION. INTRODUCTORY OBSERVATIONS.