What are the cognitive mechanisms that underlie selfless conduct, both ‘thinking’ and unthinking? We first consider deliberate selflessness, a manner of selecting acts in which, in evaluating options, one expressly chooses not to weigh the potential consequences for oneself (though this formulation is seen as needing some qualification). We then turn to unthinking behavior in general, and whether we are responsible for it, as the foundation for analyzing the unthinking variety of selflessness. Using illustrative cases (Grenade Gallantry, The Well-Meaning Miner, (...) Ignorant Ilya, Self-Disregarding Sally) we explore just what is involved in setting aside one's self-interests unthinkingly. Eventually, this account links up with work on mental compartmentalization, as it becomes apparent that unthinking selflessness encompasses both unthinking behavior (calling upon inexplicit cognitive utilization of stored images) that is selfless, and thinking behavior (calling upon reasoning with sentences) that is unthinkingly selfless (by virtue of an unreasoned, automatic shift of cognitive standpoint to a ‘compartment’ that omits information about one's self-interests). The analysis points toward a practical program for generating increased selflessness in ourselves and others. (shrink)