how about .. "we are but mechanisms to accumulate layers of matter so that a brain emerges. each brain tries to make sense of the universe, and this is a terribly attenuating thing,  so the brain wears out, rather, the material accumulation is not enough to keep the brain 'playing the latest version of the game', so the already accumulated material layers sanction a branch-off operation with lesser/different 'sense' so that the new brain can start where the old one left off ..,  parallely dialing down resource allocation to the existing piles of material"