Charles W. Morris
Thomas A. Sebeok (1920–2001), a student of Charles W. Morris, was a prolific and wide-ranging American semiotician. Although he insisted that animals are not capable of language, he expanded the purview of semiotics to include non-human signaling and communication systems, thus raising some of the issues addressed by philosophy of mind and coining the term zoosemiotics. Sebeok insisted that all communication was made possible by the relationship between an organism and the environment in which it lives. He also posed the equation between "semiosis" (the activity of interpreting signs) and "life"—a view that the Copenhagen-Tartu biosemiotic school has further developed.