In which I offer some physical insights into the difference between a physicalist and an idealist metaphysical approach.

One of the most striking aspects of Kant’s Critique to the student of physical sciences is a seeming pre-empting of Einstein’s relativity and other twentieth century advances in theory. In particular I refer to the central thesis that our conceptions of time and space preempt and facilitate experience. It is almost certainly true that Einstein was totally unaware of Kant’s work, but nevertheless his advances might seem to rest upon the key idea that 4 dimensional space-time is a framework with which to interpret sensory data and not built upon sensory data from purely logical principles. Otherwise how could he become convinced of un-common-sense new representations.

Consider the following system: A three dimensional Euclidean space-time in which a two dimensional space develops in time. Point particles evolve continuously over time. In any instant velocities are never infinity. Now let us give each particle an ‘internal coordinate’. Each particle can be defined by two spatial coordinates and a further physical property x. The question I am going to ask here is ‘how do physical theories in this universe differ if x is some physical quantity such as mass compared to if it is a third spatial dimension?’. Regardless of whether or not the latter would essentially be a coordinate transformation leading to a mathematically more complicated set of governing equations (dependent on the forces operating in the universe) this must be accepted as a possible representation. For instance consider a classical gravitation simulation with two bodies. One can consider the two bodies as having 4 coordinates which vary in time (3 spacial and one mass). Obviously mass is fundamentally different from the three spacial coordinates (it is constant for a given body/it plays a very different algebraic role in the governing equations). My claim here is that although the current representation of three spacial dimensions is the simplest in terms of the algebraic size of the governing equations, it is not a unique representation.

If you accept the proposed scheme laid out in the previous paragraph, then will you accept it leads to the following broader statement:

“The common sense descriptions of reality built originally upon forces acting on particles in four dimensional space-time is one of a set of greater than one representations.”

And finally if you would accept the arguments laid forth here, could you accept the following possibility:

The common sense representation of the world which precedes and makes possible experience built on sensory data is determined by the evolutionary principle that the models used to represent the world in consciousness are those models which require the smallest brains (in terms of energy expended in production).

If one can accept that that final un-empirical statement (I know of no experimental evidence for it) is a logical possibility then one has moved some way to a rejection of physicalism.