Abstract
Morgan’s original canon (1894) was intended as a prophylactic against an anthropomorphic bias that he thought stemmed from the double inductive method, which explains seemingly identical behavior in animals and humans in terms of the same underlying causes. However, his defense of the method of variation, which introduces a bias of its own towards type-2 errors (Sober 2005), as well as the original canon’s reliance on vague terms like ‘higher’ and ‘lower’ psychical faculties, has been repeatedly reinterpreted and contested throughout the history of comparative psychology (e.g., Karin-D’Arcy 2005; Allen-Hermanson 2005; Meketa 2014; Heyes 2012; Fitzpatrick 2008). Despite these perennial disputes, Morgan’s canon has played a preeminent role in the methodology of comparative psychology, even if it is unclear what it precisely means or how exactly it should be used to direct research. This has frequently led to uncritical invocations of the canon to settle the task of theory selection when it is unsuited to do so. This talk is directed at ameliorating some systematic problems that pervades comparative psychology's use of the canon. I do this by developing a quantitative parsimony interpretation of Morgan’s canon, while simultaneously laying out the conditions for interpreting the evidential strength of individual invocations and showing how they can be evaluated against one another. On this interpretation, a theory or model is more parsimonious than another, if the fact that there is less of a local relevant feature gives us reason to prefer it. A theory or model establishes its relevant simplicity against a context to which it is bound, where being bound to a context implies being committed to counting in a certain way (Sober 1994). This implies that are multiple ways in which being simple in a certain way is relevant both within and across contexts (Okasha 2011, Kuhn 1962). For example, as Dacey (2016) highlights, the target of parsimony claims and invocations of Morgan’s canon include processes, energetic demands, structures, and inputs. Given that such claims are local and multiple, I offer a way of evaluating incompatible claims based on their justificatory strength and their degree of underdetermination. Doing so offers a principled way to direct further research that can account for both empirical as well as extra-empirical concerns. On this interpretation, the original spirit of Morgan’s canon can be preserved in so far as invocation of it employs a more fine-grained interpretation of both the purported simplicity claim underlying it and the demands of the mental continuity thesis that gave rise to it. Moreover, this interpretation foregoes the pitfalls of so-called ‘default’ reasoning that are pervasive in the discipline, while addressing the problems of both anthropomorphism, anthropodenialism, as well as uncritical invocations of the mental continuity thesis. References Allen-Hermanson, S. .2005. Morgan’s Canon Revisited. Philosophy of Science. 72(4):608-631. Dacey, M. 2016. The Varieties of Parsimony in Psychology. Mind & Language. 31(4):414-437. Fitzpatrick, S. 2008. Doing Away with Morgan’s Canon. Mind & Language. 23(2):224-246. Karin-D’Arcy, M. 2005. The Modern Role of Morgan’s Canon in Comparative Psychology. International Journal of Comparative Psychology. 18(3). Kuhn, T. S. [1962] 2012. The Structure of Scientific Revolutions: 50th Anniversary Edition. University of Chicago Press, Chicago, Il. Heyes, C. 2012. New Thinking: The Evolution of Human Cognition. Philosophical Transactions of the Royal Society B: Biological Sciences. 367(1599):2091-2096. Lloyd Morgan, C. 1894. An Introduction to Comparative Psychology. The Walter Scott Publishing Co, Ltd. London and Newcastle-on-Tyne. Meketa, I. 2014. A Critique of the Principle of Cognitive Simplicity in Comparative Cognition. Biology and Philosophy. 29(5):731-745. Okasha, S. 2011. Theory Choice and Social Choice: Kuhn versus Arrow. Mind. 120(477):83- 115. Sober, E. 1994. From a Biological Point of View: Essays in Evolutionary Philosophy. Cambridge University Press, Cambridge, UK. Sober, E. (2005). Comparative Psychology meets Evolutionary Biology. In L. Datson and G. Mitman (eds.), Thinking with Animals: New Perspectives on Anthropomorphism. Columbia University Press, New York, NY, pp. 85-99.
