[55] System of Logic, vol. i, Bk. III, ch. vi.
[56] Problems of Life and Mind, Series II, p. 212.
[57] Of course if a particular physico-chemical change (a) is correlated with a particular physiological or vital change (b), then (b) implies (a) as (a) implies (b). The statement in the text refers to the implications of classes of change. There may be physico-chemical relatedness without any correlated vital relatedness; but there does not appear to be any vital relatedness which is not correlated with physico-chemical relatedness.
[58] Essays, vol. iii, pp. 31, 55.
[59] Ps., vol. ii, p. 484.
[60] F. P., p. 178.
[61] An ordinal correlation is one that couples every term of a series (a) with a specific term of another series (b) and vice versa in the same order in each. Cf. Spaulding in The New Realism, p. 175. I shall sometimes speak of such correlation as serial.
[62] Principles of Biology, Edition of 1898, pp. 117, 120.
[63] Op. cit., p. 122.
[64] Ps., vol. i, p. 208.