Twin and adoption studies have revealed that a disposition toward suicidal behavior is partially heritable.
The first is conscientiousness, which entails a disposition to be diligent, organized, and responsible.
late 14c., "ordering, management," also "tendency of mind," from Old French disposicion (12c.) "arrangement, order; mood, state of mind," from Latin dispositionem (nominative dispositio) "arrangement, management," noun of action from past participle stem of disponere "to put in order, arrange" (see dispose). References to "temperament" (late 14c. in English) are from astrological use of the word for "position of a planet as a determining influence."