As we have seen by the example of Herbert Spencer, it is difficult not to go from empiricism to criticism. But can Criticism itself claim to have said the last word concerning science? It would seem not, in view of the fact that out of Criticism there arose in Germany the boldest dogmatism the world has yet seen. Kant's great merit is that he transferred the problem to the nature and the conditions of thought; but the reflection on thought to which this point of view invites us, at the same time furnishes principles which permit us to go beyond it (see F. Ravaisson, Rapport sur le prix Victor Cousin).

CHAPTER II

MATTER

METAPHYSICS is the science of first principles and of first causes (Arist. Met. I, 1, Ch. II). It reaches back to principles which pre-suppose no further principles, and to the cause, or causes, which have no other cause. Whatever their particular theories may have been, those philosophers who professed to reduce the universe to its principles of existence have had to account for the unity and diversity revealed to us by the observation of phenomena. The one and the many, activity and passivity, perfection and limitation, are everywhere found mingled in the world, which is the object of our thought. Hence arose the hypothesis of a passive and manifold principle, namely matter, and of a principle of movement and unity, which is the soul, and the necessity of explaining the intercommunication and interaction of these two principles whose union is apparently contradictory. It is true that some philosophers have denied the existence of matter, and others the existence of mind, but all have had nevertheless to explain the apparent dualism which the observation of things seems to impose on us. therefore consider the different metaphysical systems from the point of view of the solution they offer to the problems of matter and of mind, and of the relations between them.

We may

Hylozoism of the First Philosophers. Atomism of Democritus. We should seek in vain among the first Greek philosophers, always excepting Democritus and the Atomists, for a clear and

distinct conception of matter as we understand it. These philosophers considered all things, as Aristotle puts it, ev üλns eidet, "from the point of view of matter," but the conception they formed of matter was still confused and involved. The elements, which they took as constitutive principles of the physical world, were partly material and partly spiritual, and the mode according to which these elements are combined was with most of them, whatever Ritter may say to the contrary (see his History of Greek Philosophy), neither strictly dynamic nor expressly mechanical.

Take for instance Thales, the first Ionic Philosopher. According to him the substance of things was water, or in a general way a humid element (Arist. Metaph. I, iii, 983 b, 20), but this element was not purely material, it had a soul, ux (De Anima, I, v, 411 a, 7). Nor was it, properly speaking, spiritual, for this soul is, as it were, an undefined attractive and motor force, something like a magnet (Ibid. I, ii, 405 a, 19). Thus, Thales' conception was rather a confused kind of hylozoism; and one may say the same of the "Infinite" of Anaximander, of the "air" of Anaximenes. Anaximenes aera deum statuit esseque immensum, et infinitum, et semper in motu (Cic. De Nat. Deorum I, 10).

The conception of Heraclitus shows more originality. Not that he rises above the purely physical point of view of his predecessors; it is a grave historical error to represent him as the precursor of Hegel, as Lassalle does (Die Philosophie Heracleitos des Dunklen, 2nd vol.). The universal principle of being is an ever-living fire, which is ignited and extinguished in accordance with a fixed rhythm: πῦρ ἀείζωον, ἁπτόμενον μέτρῳ καὶ ἀποσβεννύμενον μέτρῳ (Frag. 27). Fire becomes all things, and all things turn into fire (Frag. 49). Fire is not indeed a determinate sensible existence, but the common substratum, the substance of all sensible things.

It would seem at first sight that with Pythagoreanism the principle of the explanation of things becomes decidedly spiritual, but the Pythagorean Number must be regarded as an element (σToXcov, Arist. Metaph. I, v, 985 b, 28), as the substance or material out of which things are made. Numbers are divided into odd numbers (Teρiσσá), even numbers (apria), and oddeven numbers (aрTIоTéρioσα). The odd is identified with the

(ἀρτιοπέρισσα).

limited, the even with the unlimited. The formula, "everything is Number," is then equivalent to the following: Everything is formed either of things limiting or of things unlimited, or of things that are both limiting and unlimited. ȧváyka Tà ἐόντα εἶμεν πάντα ἢ περαίνοντα ἢ ἄπειρα, ἢ περαίνοντά τε καὶ άπeiра (Frag. of Philos. 3). These opposite elements are united in Number. Number is thus a principle of unity and harmony. The only difference between the Pythagoreans and the Ionic philosophers is that the former seek the essence of matter, not in a single more or less subtle or dense material principle, but in Number, the most abstract principle, which they conceived as being the synthesis, the harmony, of the two opposite elements, the limited and the unlimited.

Parmenides attacks the vulgar conception of matter as multiplicity and motion. Being alone exists: Being that is one, immovable, full, always like unto itself (V, 60). Parmenides calls this Being a sphere, not as a mere poetical comparison, but as being really identical with a sphere (V, 103, 104). Matter and thought are not distinguished by him, both are contained in the conception of Being in general (V, 39, 40). The Eleatic philosophy marks, however, an important stage in the history of the theories of matter, for in it phenomena, the ephemeral modes, are for the first time distinguished from the substantial and permanent element. We shall see how, later on, philosophers returned to the Eleatic principles, and drew from them new consequences.

Empedocles holds with Parmenides that birth and destruction are mere appearances (V, 113 sq.). What appears to us to be a birth or becoming (púois), is merely a mixture of elements (uîşıs). What we regard as annihilation (TeλEUTý) is merely a separation of elements (diáλλağıç) (V, 98 sq.): the primordial elements, the piluara of things are four water, air, earth, and fire. How does the mixture take place? The particles of a body detach themselves from the group to which they belong, to penetrate into the pores (Topo) of another body. A new substance is not formed, there is only a displacement or re-arrangement of the elementary particles. As for the action at a distance of one body upon another, it is explained by what Empedocles calls emanations (άoppoαí) : some infinitely small, invisible particles are detached from one

body and penetrate into the pores of another (V, 337). This action takes place more easily according as there is a greater similarity between the two bodies: for there is an affinity, a friendship between similar things (Arist. De Gen. et Corr. I, 8).

Anaxagoras, like Empedocles, regards birth and death as a union and separation (Fr. 17). But the primary substances (σTéρμаTα) are, according to him, infinite in number. These σTéρμата are not indeterminate, like the atoms of Democritus, they are at once perfectly definite and endlessly various in qualities (Fr. 3). A bone, for instance, is composed of smaller bones which have come together and combined (Lucretius, I, 834-39). Aristotle calls those elements “like” (Tà ôμoloμepî), whose combination forms the different bodies. (De Gen. et Corr. I, i, 314 a, 18.)

The clearest expression of the materialistic theory to be found in philosophy, is the one given by the Atomists Leucippus and Democritus. They grant to the Eleatics that motion and becoming are impossible without Non-being, but instead of inferring from this proposition the impossibility of motion and of becoming, they deduce from it the reality of Non-being. Nonbeing exists by the same right as Being. Being, which the Atomists, like the Eleatics, identify with the plenum, тò πλîρes, is composed of atoms, that is to say, of indivisible particles, which are eternal, qualitatively indeterminate, in number infinite, and separated from one another by Non-being or the Void, τὸ κένον. For the cause of the motion of matter Empedocles had fallen back upon the mythical forces, love and hate, while Anaxagoras found this cause in the action of intelligence. But according to Democritus the principle of motion is not to be found in any force external to the atoms (Arist. De Caelo, III, 2), but in a preceding motion, and so on to infinity. This motion does not, however, occur at random, but in obedience to necessary and fixed laws: οὐδὲν χρῆμα μάτην γίγνεται, ἀλλὰ πάντα ἐκ λόγου τε καὶ ὑπ' ἀνάγκης (Frag. 41).

Thus everything is reduced to atoms and motion: the manner of the grouping and combination of the atoms, the primary qualities, i.e. extension and weight, constitute the essence of things. As for the secondary qualities (heat, cold, taste, smell), they come not from the object itself, but from the impression it produces on human sensation.