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self-interest vs. selfishness

[self-in-trist, self-, -in-ter-ist] / ˌsɛlfˈɪn trɪst, ˈsɛlf-, -ˈɪn tər ɪst /

noun

  1. regard for one's own interest or advantage, especially with disregard for others.

    He appears to be motivated solely by self-interest, greed, and an insatiable hunger for self-aggrandizement.

  2. personal interest or advantage.

    It is particularly hard to understand why a group would vote against its own self-interest.

  3. Economics. the doctrine that acting to one’s own benefit or advantage can also result in a benefit for society at large.

    Adam Smith believed that individuals pursuing rational self-interest would create wealth through efficient production and competition.

[sel-fish-nis] / ˈsɛl fɪʃ nɪs /

noun

  1. the quality or state of caring only for oneself or one’s own interests.

    The author rants at length about the selfishness and general disregard for others that he sees at the root of modern society.