Psychology: A Newtonian science of mind

Lateral thinkers interested in the mind have been inspired by the methods and results of physics for a long time. For example, the British empiricist philosopher John Locke (*1632; †1704) was imbued with the corpuscular theory of light (primarily formulated by his friend Sir Isaac Newton) when he formulated his “corpuscular theory of ideas” in his profoundly influential publication “An essay concerning human understanding” which appeared in 1690. Locke transferred and generalised the axioms of Newtons physical theory (which concerned the lawful behaviour of matter) to the psychological (nonmaterial) domain. In other terms, Locke committed himself to a reductionist Newtonian science of the mind (Ducheyne, 2009). Corpuscularianism is an ontological theory which postulates that all matter is assembled of infinitesimally small particles (Jacovides, 2002). This notion is similar to the theory of atomism, except that, in contrast to atoms (from the Greek átomos, “that which is indivisible”), corpuscles can theoretically be further subdivided (ad infinitum). According to Newton, these corpuscles are held together by a unifying force which he termed “gravitation” (Rosenfeld, 1965). One of Locke’s primary concerns in this regard was: What are the most elementary “particles” of human understanding (i.e., what are the “atoms of thought”), where do they come from, and how are they held together? Locke rejected the Cartesian notion of innate (God-given) ideas, but he accepted some intuitive principles of the mind (e.g., the law of contradiction) which he assumed must be in place a priori in order for any knowledge to arise.
In addition to this kind of intuitive knowledge about propositional logic, which he conceptualized as immediate, indubitably knowable and certainly true, Locke also accepted some forms of demonstrative knowledge to be certainly true. For example, the axioms of Euclidean geometry. In contrast to intuitive knowledge, one has to perform a series of mathematical proofs in order to reach a certain general conclusion which is true in all contexts and circumstances. Having defined these principles he pursued his initial question: What are the most elementary “particles” of human cognition, where do they come from, and how are they held together? Locke’s answer is simple: Ideas come from experience and are held together by associational forces (Halabi, 2005). That is, empirical knowledge which is accumulated diachronically during the course of a lifetime forms the basis of thought. Locke argues that the most elementary act is the sensory act and the most elementary contents of the mind are sensations. He remarks:

“For to imprint anything on the mind without the mind’s perceiving it, seems to me hardly intelligible”
(Chapter 2 – On innate ideas)

In other words, what enters the mind comes through the sensorium and these elementary sensations must be connected somehow. According to Newton, the corpuscular components of reality are held together by gravitational forces, i.e., Newton’s law of universal gravitation which follows the inverse-square law.
Locke ingeniously applied this idea to elementary sensations and proposes the principle of “association” as the mental counterpart to physical gravitation. Ex hypothesi, objects or events which are frequently experienced together are connected by associative processes. They thereby recombine to form simple ideas. Out of simple ideas, increasingly complex ideas are hierarchically assembled by the binding force of association – this the Lockean associative “logic of ideas” (Yolton, 1955). The Lockean associationist memetic account is still viable today. e.g., associative (Bayesian) neural networks in artificial intelligence research.