If we had made this experiment with two people A and B, and A had applied the expression “the same tone” to the octave only, B to the dominant and octave, should we have a right to say that the two hear different things when we play to them the diatonic scale? ‒ ‒ If we say they do, let us be clear whether we wish to assert that there must be some other difference between the two cases besides the one we have observed, or whether we wish to make no such statement.