ABSTRACT
Despite a variety of critiques (e.g., de Waal 1999; Sober 1998, 2005; Fitzpatrick 2008; Andrews and Huss 2014; Meketa 2014; Starzak 2016), the principle known as Morgan’s Canon retains a significant hold on modern scientific and philosophical discussions of nonhuman animal (henceforth, “animal”) cognition and behavior. Proposed by the late-nineteenth-century British philosopher-psychologist, Conwy Lloyd Morgan – generally regarded as the “father” of modern comparative psychology – it states that:
In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale.
(Morgan 1894: 53) Morgan saw this principle as necessary for scientifically rigorous investigation into the minds of animals. It went on to exert enormous influence on the subsequent development of comparative psychology, though not always in ways consistent with Morgan’s original intent (Costall 1993; Thomas 1998; Fitzpatrick and Goodrich 2016).