central blindness of, in twilight, [60];
compared with olfactory membrane, [63].
Rhythm, perception of, [123], [125], [159] f.;
subjective, [104];
helps to establish associative tendencies, [153];
in mnemonics, [193].
Saturation, of colours, [57].
Science, has no concern with values, [1] ff., [22], [325];
is no respecter of persons, [2] f.;
makes impersonal and disinterested search for facts, [2] f., [4], [30] f., [39], [48], [275], [313], [325], [330];