Maudsley's classification, according to the faculties thought to be affected, {106} is also inconsistent: I. Affective insanity: (1) Simple mania; (2) simple melancholia; (3) moral insanity. II. Ideational insanity: (1) General (acute and chronic mania and melancholia); (2) partial (monomania and melancholia); (3) dementia (primary and secondary); (4) general paralysis; (5) idiocy and imbecility. The classification according to symptoms is most generally adopted, being used, more or less modified, in Germany, generally in France, and more commonly than any other in this country and in England. It has been suggested by different writers in a dozen different forms, differing only in details. Griesinger's is as follows: (1) States of mental depression: Hypochondriasis; simple melancholia; melancholia with stupor; melancholia with destructive tendencies; melancholia with persistent excitement of the will or impulse (moral insanity). (2) States of mental exaltation: Mania; monomania. (3) States of mental weakness: Chronic mania; dementia; idiocy; cretinism. As important complications of insanity he places general paralysis of the insane and epilepsy, and various disorders of sensation and movement, such as convulsive gait, general cramps, choreic movements, hyperæsthesia of the skin, etc. A classification according to the morbid condition of the brain has thus far proved unsuccessful. Up to the present time this remains largely a field of speculation, and even with the immense progress of the past dozen years it is a subject upon which there is now little definite to be said. Voisin's system is purely visionary—namely: I. Idiopathic insanity, due to vascular spasm. II. Insanity dependent on brain lesions: Congestive insanity; insanity from anæmia; atheromatous insanity; insanity from brain tumors. III. Insanity from alterations of the blood: Diathetic insanities; syphilitic insanity. In basing his nomenclature on the clinical history of the various forms of insanity, Clouston makes his classification as follows: (1) States of mental depression (melancholia, psychalgia): (_a_) Simple melancholia; (_b_) hypochondriacal melancholia; (_c_) delusional melancholia; (_d_) excited melancholia; (_e_) suicidal and homicidal melancholia. (2) States of mental exaltation (mania, psychlampsia): (_a_) Simple mania (folie raisonnante); (_b_) acute mania; (_c_) delusional mania; (_d_) chronic mania. (3) States of regularly alternating depression and exaltation (folie circulaire, psychorhythm, folie à double forme, circular insanity, periodic mania, recurrent mania). (4) States of fixed and limited delusion (monomania, monopsychosis): (_a_) Monomania of pride and grandeur; (_b_) monomania of unseen agency; (_c_) monomania of suspicion.