An 1817 British Admiralty map of Kolpos Kallonis, the lagoon in Greece where Aristotle began the study of the biological world. Aristotle proposed that organisms were formed and maintained by their “souls,” by which he meant the topography of their metabolic and regulatory networks. Superimposed within the lagoon, therefore, is a map of the regulatory network of a yeast cell: Aristotle’s vision realized in the 21st C.