 In the Essay, Condillac had identified the use of language as necessary for higher cognitive functions, including memory, the control of the imagination, and reflection. Animals, which at best have the use of natural signs, can only recall (imagine) absent objects if a present object has been habitually associated with them. Unable to use at will signs standing for absent objects, they are without memory. Thus they live from moment to moment, without any proper notion of a continued past existence in which various events are connected. Everyday is like a new day for them, and they simply repeat habitual patterns of behaviour most conducive to their survival. They are at best capable of what Condillac calls ‘reminiscence’ and thus they can recognize an object as previously experienced. The case of a boy who grew up among bears in the woods between Lithuania and Poland appeared to provide confirmation for animals’ mental inferiority: found unable to speak, this youth only gradually learned the language, and afterwards could not recall his past life nor did he have any notion of having spent many years in the woods (Essay I.iv.2 §§23-25). Another case, that of a deaf-and-dumb boy who suddenly recovered his hearing, further confirmed Condillac’s hypothesis: after a period of learning, the boy confirmed that while he was deaf he could not attach any meaning to the sign of the cross that he saw his parents doing, nor did he have any notion of death, life after death, or God (Essay I.iv.2 §§13-22). (Condillac regretted that the examiners of the case had asked the boy merely about his religious beliefs.) Subsequently, as is evident in his correspondence with Cramer and Maupertuis, Condillac had come to believe that he had drawn too sharp a line between lower and higher cognitive functions and that thus he had in effect reintroduced a dualism of reason and sensation in the mind.