小 ina minds from the historica」 perspective Aristotle: defined human"as the rational animal thus rejecting the possibility that any other species is rational Aquinas: believed that animals are irrational because they are not free Descartes: defended a distinction between humans and animals based on the belief that language is a necessary condition for mind on his view animals are soulless machines Kant: concluded that since they cannot think about themselves animals are not rational agents and hence they only have instrumental valueAnimal Minds from the historical perspective :  Aristotle: defined “human” as “the rational animal”, thus rejecting the possibility that any other species is rational.  Aquinas: believed that animals are irrational because they are not free.  Descartes: defended a distinction between humans and animals based on the belief that language is a necessary condition for mind; on his view animals are soulless machines.  Kant: concluded that since they cannot think about themselves, animals are not rational agents and hence they only have instrumental value