 To have beliefs, Dretske suggests, is to have an integrated manifold of such representational systems, acquired in part through associative learning, poised to guide behavior. Given the lack of such a complex, and the lack of associative learning, magnetosome bacteria cannot, on Dretske’s view, rightly be regarded as literally possessing full-fledged beliefs. But exactly how rich an organism’s representational structure must be for it to have beliefs, and in what ways, Dretske does not address, regarding it as a terminological boundary dispute, rather than a matter of deep ontological significance. (For more on belief in non-human animals see §4 below.)