• C. Lloyd Morgan is mostly known for Morgan’s canon (1894), still a popular and frequently quoted principle in comparative psychology and ethology. There has been a fair amount of debate on the canon’s interpretation, function, and value regarding the research on animal minds, usually referring to it as an isolated principle. In this paper we rather shed light on Morgan’s overall scientific program and his vision for comparative psychology. We argue that within his program Morgan identified crucial conceptual, ontological, and methodical issues, that are still fundamental to the current research on animal minds, and we contend that a proper understanding of the canon can only be gained taking it as part of this program. This also highlights a new aspect of his role as one of the ” founding fathers ” of modern comparative psychology. In order to understand Morgan’s program, we briefly outline the historical context in which he began his work on a science of comparative psychology. We will then emphasize to what extent his taxonomy of psychological capacities, the development of his metaphysics for a comparative psychology, and his newly introduced interdisciplinary procedures justify Morgan’s distinctive approach to still rather sensitive issues. In doing so, we aim to provide a more comprehensive picture of Morgan’s methodological signature. We finally understand his most renown considerations as part of his struggle to ascertain the limits and possibilities of the discipline he contributed to set up, and thus emphasize the need to keep the discussion going, notably on the accessibility of other minds than one’s own and on the limits of one’s research perspectives.