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Friendship is only a reciprocal conciliation of interests, and an exchange of good offices; it is a species of commerce out of which self-love always expects to gain something.

"The Moral Maxims and Reflections". Book by François de La Rochefoucauld. Maxim 83, 1678.
Friendship is only a reciprocal conciliation of interests, and an exchange of good offices; it is a species of commerce out of which self-love always expects to gain something.