The mathematical model of attention dynamics and attention control is being developed, in continuation of the previous work, and the concepts of voluntary and involuntary attention, and of volition are introduced, in particular. Volition is being mathematically determined, and the will power is conceptualized as the mean value of volitions across all psychic processes involving voluntary control. The results obtained make it possible to conceptualize the processes of psychic self-control, as well as contribute to building their mathematical model.