The Causal Theory of Perception

Abstract

The causal theory of perception has been held by philosophers, psychologists, and scientists in one form or another from the pre-Socratic predecessors of Plato through the development of modern science in the seventeenth century by Boyle and Newton, to recent philosophical theories such as those held by Price, Broad and Russell. The theory has been based upon philosophical speculation combined with observation, upon the data of physiology, and recently upon the results of modern physics. Thus, it shares a wide diversity of justification. In its precise formulation, the theory advocated by this tradition of thinkers is best stated by Price. Working within the philosophical framework of the sense-datum theory, Price investigates two main aspects of the problem of perception: the way in which knowledge is obtained and the relation of ‘belonging to’ holding between sensible qualities and physical objects. In these terms, the causal theory maintains (1) “that in the case of all sense-data (not merely visual and tactual) ‘belonging to’ simply means being caused by, so that ‘M is present to my senses’ will be equivalent to ‘M causes a sense-datum with which I am acquainted’,” and (2) “that perceptual consciousness is fundamentally an inference from effect to cause.”¹ Attributing the theory to science, Russell describes it in almost identical terms.