This mechanism, so simple, so natural, suffices to demonstrate, why uncertainty is painful; why suspense is always a violent state for man. The brain, an organ so delicate, so mobile, experiences such rapid modifications, that it is fatigued; or when it is urged in contrary directions, by causes equally powerful, it suffers a kind of compression, that prevents the activity which is suitable to the preservation of the whole, which is necessary to procure what is advantageous to its existence. This mechanism will also explain the irregularity, the indecision, the inconstancy of man; and account for that conduct, which frequently appears an inexplicable mystery, which indeed it is, under the received systems. In consulting experience, it will be found that the soul is submitted to precisely the same physical laws as the material body. If the will of each individual, during a given time, was only moved by a single cause or passion, nothing would be more easy than to foresee his actions; but his heart is frequently assailed by contrary powers, by adverse motives, which either act on him simultaneously or in succession; then his brain, attracted in opposite directions, is either fatigued, or else tormented by a state of compression, which deprives it of activity. Sometimes it is in a state of incommodious inaction; sometimes it is the sport of the alternate shocks it undergoes. Such, no doubt, is the state in which man finds himself, when a lively passion solicits him to the commission of crime, whilst fear points out to him the danger by which it is attended: such, also, is the condition of him whom remorse, by the continued labour of his distracted soul, prevents from enjoying the objects he has criminally obtained. If the powers or causes, whether exterior or interior, acting on the mind of man, tend towards opposite points, his soul, is well as all other bodies, will take a mean direction between the two; in consequence of the violence with which his soul is urged, his condition becomes sometimes so painful that his existence is troublesome: he has no longer a tendency to his own peculiar conservation; he seeks after death, as a sanctuary against himself--as the only remedy to his despair: it is thus we behold men, miserable and discontented, voluntarily destroy themselves, whenever life becomes insupportable. Man is competent to cherish his existence, no longer than life holds out charms to him; when he is wrought upon by painful sensations, or drawn by contrary impulsions, his natural tendency is deranged, he is under the necessity to follow a new route; this conducts him to his end, which it even displays to him as the most desirable good. In this manner may be explained, the conduct of those melancholy beings, whose vicious temperaments, whose tortured consciences, whose chagrin, whose _ennui_, sometimes determine them to renounce life.