Description:
"Prior to Darwin humans lived in a different world from other species. While our machines were inhabited by ghosts, other creatures were simply machines devoid of internal states (Descartes, 1641). With the publication of the Origin of Species in 1859, however, people began to question this anthropocentric assumption of a discontinuity between 'us' and 'them'. Thirteen years later in Darwin's final book The Expression of the Emotions in Man and Animals he developed this argument of continuity between human and non-human species further by drawing on observations of parallels of expression and reaction in a wide range of species. It is fair to say that The Expression of the Emotions led directly to the development of 'comparative psychology' and provided legitimacy to the study of animal behavior as a means to better understand ourselves (Workman, 2013). In 1894 Conway Lloyd Morgan formalised this approach in his book Introduction to Comparative Psychology setting out the ground rules for the comparative method"--