In its simplest form, actions performed for no measurable reason, or contrary to linear logic, might indicate such underlying motives as love or friendship or trust. But great care had to be exercised, because identical actions could derive from hate, insanity, or blackmail. Moreover, in the case of love, the nature of the action seldom helps to identify its motivational impulse. Particularly difficult is separating love from blackmail.
Trevanian, Shibumi: A Novel [Amazon, Bookshop, Publisher, Local Library]