Hate then may be taken to exemplify the principle of antithetic evolution. We are careful not to raise the anger of some men and of some animals, and thus anger, or the capacity for anger, serves them as advantage and defence. We fear to make them mad. However, the antagonists of many individuals, knowing the weakening effect of such a strong emotion as anger, and knowing also how apt the angry one is to “lose his head,” purposely stimulate anger to their own advantage, and the disadvantage of the angered. Thus, cunning and wary animals, impelled by hate, often tease and torment their stronger and larger adversaries and competitors into a furious rage, which is so rash and unintelligent that they are completely at the mercy of the weaker. Where in such a way as this an advantageous variation is turned into disadvantageous by an opposing form, as anger by hate, we have what may be called an antithetic evolution. New psychic variations are then continually stimulated by the earlier, and it is only for a short time that any variation maintains itself as purely beneficial, but an answering one soon takes advantage of its weak points and turns it from self-conservative into self-destructive. Under the constant success of opposing factors, there is gradual loss of value and soon disuse, with the inception of some new form to combat more effectively the opponent. This opposing form meanwhile attains dominancy, culminates, and is gradually ousted by some variation which has been attained in order to meet the new weapons on the other side. Thus, in the battle of life, offence and defence, attack _versus_ retreat and counter-attack, mutually stimulate to a series of new and higher antithetic psychic variations.