Any attempt to classify and to understand the basic mechanism underlying the neurological symptoms as pyramidal and/or sensitive, should start from the fundamental laws of nervous system functioning: 1) the law of reciprocal innervation of Sherrington; 2) the law of hierarchy of levels of Jackson and 3) the law of supersensitivity of deafferented structures of Cannon. Paresis on one side, Jacksonian jerks on the other side represent two opposite conditions known respectively as negative and positive symptoms of corticomotor involvement. Unluckly involuntary movements cannot be explained with these three laws. They are the clinical expression of the disorganization and disintegration of functions: a true disregulation unrespectful of laws and general principles. They must be considered as the result of conflicts of antagonist functions controlling each other, i.e. tremor, chorea, myoclonus, torsion spasm etc. The author emphasizes the clinical-descriptive aspect of the problem.