Bion created a theory of thinking based on changing beta elements (unmetabolized psyche/soma/affective experience) into alpha elements (thoughts that can be thought by the thinker). Beta elements were seen as cognate to the underpinnings of the "basic assumptions" identified in his work with groups: "the fundamental anxieties that underlie the basic assumption group resistances were originally thought of as "proto-mental phenomena"...forerunners of Bion's later concept of beta-elements." They were equally conceptual developments from his work on projective identification—from the "minutely split 'particles'" Bion saw as expelled in pathological p.i. by the psychotic, who would then go on to "lodge them in the angry, so-called bizarre objects by which he feels persecuted and controlled". For "these raw bits of experience he called beta-elements...to be actively handled and made use of by the mind they must, through what Bion calls alpha-functions, become alpha-elements".