The term psychology is from the 1650s, "study of the soul," from Modern Latin psychologia, probably coined mid-16c. in Germany by Melanchthon from Latinized form of Greek psykhē "breath, spirit, soul" (see psyche) + logia "study of" (see -logy).

Psychology in negotiations has its roots deep into interactions between humans. Specifically, most of the identified influence tactics operate on either altering the counterpart’s incentives and/or altering the counterpart's information set. Negotiators will often aim to build strong coalitions in order to weaken the other party’s alternatives, to engage in exchange in order to create value, and to use reason to justify offers. The effort to positively influence another party’s attitude towards a given idea or proposition without changing the incentives or objective information set of the other party. Psychological influence typically entails leveraging an understanding of psychological biases and heuristics in order to frame ideas and proposals in such a way that increases their appeal to the counterpart.

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Influencing deals, counterpart psychology, soul of incentive