What the frog's eye tells the frog's brain

This is a key paper is biological systems theory.  I took one of Jerome Letvin's courses at MIT, and later studied Ontological Design with Fernando Flores who pointed me to his teachers, Humberto Maturana and Francisco Varella.  Maturana is a co-author on the paper.

Connecting back to semiotics, this cluster of thinkers and a network around them are probably the core of what is sometimes called "biologic semiotics or systems theory".  I don't know the connection to Stafford Beer, but there has to be one if not only syncronicity.