 Now these various  formulations[27]  of WL admit, as Wundt says, of three different, and indeed incompatible interpretations; that is, there are three different conceptions of what WL is a law of. First, the physiological interpretation takes it as a manifestation of the “peculiar laws of excitation of the neural  matter;”[28]  second, the psychophysical (Fechnerian) interpretation takes WL as governing the interrelation between somatic and psychic activity (PP I: 392). Wundt rejects both of these in favor of a third, the psychological interpretation; his arguments are instructive. Against the physiological interpretation Wundt raises the following main point, viz. that