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When the satisfaction or the security of another person becomes as significant to one as one's own satisfaction or security, then the state of love exists. Under no other circumstances is a state of love present, regardless of the popular usage of the term.

Harry Stack Sullivan (1940). “Conceptions of Modern Psychiatry: The First William Alanson White Memorial Lectures”
When the satisfaction or the security of another person becomes as significant to one as one's own satisfaction or security, then the state of love exists. Under no other circumstances is a state of love present,