In the Warmth Course, Rudolf Steiner, in 14 lectures, approaches an understanding of the nature of heat, something that amongst modern physicists is only described in regard to matter as particle motion (i.e. microscopic agitation of molecules) and in regard to energy as the infra-red region of the electromagnetic spectrum. It is conventionally held that the infra-red wavelengths agitate particles into motion and these then also emit infra-red in their excited state, and that whichever aspect you are describing, heat is just another attribute of the physical universe which can be quantified like mass or velocity.
