Note 43 — Front matter

'But when we ask what this energy is, there is no answer save that it is the noumenal cause implied by the phenomenal effect.' F. P., p. 154. It is towards this and like statements that my criticism is directed. There can be no objection to the treatment, by physicists, of energy as an entity in the sense given below in note 82. Those phenomena to which 1/2 mv2 has reference are fundamental realities for physical science.