'The philosopher Thomas Nagel wrote an essay in 1974 titled, “What Is It Like To Be a Bat?”, in which he put forward perhaps the least overweening, most useful definition of “animal consciousness” ever written, one that channels Spinoza’s phrase about “that nature belonging to him wherein he has his being.” Animal consciousness occurs, Nagel wrote, when “there is something that it is to be that organism—something it is like for the organism.”'
John J. Sullivan