Among the charges made against modern philosophy, one is heard more than another. Modern philosophy, it is said, reduces everything to identity. Hence its nickname, the Philosophy of Identity. But the present discussion may teach that it is philosophy, and philosophy alone, which insists on distinguishing what is logically as well as in experience different; while the professed devotees of experience are the people who erect abstract identity into the chief principle of knowledge. It is their philosophy which might more appropriately be termed one of identity. Besides it is quite correct that there are no merely Extensive and merely Intensive magnitudes, just as little as there are merely continuous and merely discrete magnitudes. The two characteristics of quantity are not opposed as independent kinds. Every Intensive magnitude is also Extensive, and _vice versâ._ Thus a certain degree of temperature is an Intensive magnitude, which has a perfectly simple sensation corresponding to it as such. If we look at a thermometer, we find this degree of temperature has a certain expansion of the column of mercury corresponding to it; which Extensive magnitude changes simultaneously with the temperature or Intensive magnitude. The case is similar in the world of mind: a more intensive character has a wider range with its effects than a less intensive. 104.] In Degree the notion of quantum is explicitly put. It is magnitude as indifferent on its own account and simple: but in such a way that the character (or modal being) which makes it a quantum lies quite outside it in other magnitudes. In this contradiction, where the _independent_ indifferent limit is absolute _externality,_ the Infinite Quantitative Progression is made explicit--an immediacy which immediately veers round into its counterpart, into mediation (the passing beyond and over the quantum just laid down), and _vice versâ._ Number is a thought, but thought in its complete self-externalisation. Because it is a thought, it does not belong to perception: but it is a thought which is characterised by the externality of perception.--Not only therefore _may_ the quantum be increased or diminished without end: the very notion of quantum is thus to push out and out beyond itself. The infinite quantitative progression is only the meaningless repetition of one and the same contradiction, which attaches to the quantum, both generally and, when explicitly invested with its special character, as degree. Touching the futility of enunciating this contradiction in the form of infinite progression, Zeno, as quoted by Aristotle, rightly says, 'It is the same to say a thing once, and to say it for ever.'