The idealists only differed from the philosophic materialists on question of the alignment of nature in reference to mind.

But no one had any doubt that the philosophy of nature considered in itself was of the type which I have called materialism.

It is the philosophy which I have already examined in my two lectures of this course preceding the present one.

It can be summarised as the belief that nature is an aggregate of material and that this material exists in some sense _at_ each successive member of a one-dimensional series of extensionless instants of time.

Furthermore the mutual relations of the material entities at each instant formed these entities into a spatial configuration in an unbounded space.