The tone as well as the substance of this extract makes it evident that the opinions of Heraclides on questions of theoretical music must be accepted with considerable reserve. The notion that the Phrygian and Lydian scales were 'barbarous' and opposed to Hellenic ethos was apparently common enough, though largely due (as we may gather from several indications) to national prejudice. But no one, except Heraclides, goes so far as to deny them the name of [Greek: harmonia]. The threefold division into Dorian, Aeolian and Ionian must also be arbitrary. It is to be observed that Heraclides obtains his Aeolian by identifying the Aeolian of Pratinas and other early poets with the mode called Hypo-dorian in his own time. The circumstance that Plato mentions neither Aeolian nor Hypo-dorian suggests rather that Aeolian had gone out of use before Hypo-dorian came in. The conjecture of Boeckh that Ionian was the same as the later Hypo-phrygian (_De Metr. Pind._ iii. 8) is open to a similar objection. The Ionian mode was at least as old as Pratinas, whereas the Hypo-phrygian was a novelty in the time of Heraclides. The protest which Heraclides makes against classifying modes merely according to their pitch is chiefly valuable as proving that the modes were as a matter of fact usually classified from that point of view. It is far from proving that there was any other principle which Heraclides wished to adopt--such, for example, as difference in the intervals employed, or in their succession. His 'differences of kind' ([Greek: tas kat' eidos diaphoras]) are not necessarily to be explained from the technical use of [Greek: eidos] for the 'species' of the octave. What he complains of seems to be the multiplication of modes--Hyper-mixolydian, Hyper-phrygian, Hypo-phrygian--beyond the legitimate requirements of the art. The Mixo-lydian (_e.g._) is high-pitched and plaintive: what more can the Hyper-mixolydian be? The Hypo-phrygian is a new mode: Heraclides denies it a distinctive ethos. His view seems to be that the number of modes should not be greater than the number of varieties in temper or emotion of which music is capable. But there is nothing to show that he did not regard pitch as the chief element, or one of the chief elements, of musical expression. The absence of the name Hypo-lydian, taken with the description of Hypo-dorian as 'below the Dorian,' would indicate that the Hypo-dorian of Heraclides was not the later mode of that name, but was a semitone below the Dorian, in the place afterwards occupied by the Hypo-lydian. This is confirmed, as we shall see, by Aristoxenus (p. 18). § 7. _Aristotle--the Politics._