In the middle ages 91

standing of all things through their fundamental

and universal reasons/*^"

The thirteenth century directs us to the signifi-

cance of synthesis or generality which belongs to

philosophy, by taking up and completing Aristo-

tle's famous division of philosophy, which was ac-

cepted as valid down to the time of Wolff in the

seventeenth century. Philosophy is first, theoreti-

cal, second, lyractical, and third, poetical. This

threefold division of philosophy into speculative,

practical, and poetical is based upon man's differ-

ent contacts with the totality of the real, or, as it

was put then, with the universal order.

Speculative or theoretical (Oeuipeiv^ to consider)

philosophy gives the results of acquaintance with

the world in its objective aspect; it includes the phi-

losophy of nature, mathematics, and metaphysics,

which consider (consider at sed non facit) change,

quantity, and the general conditions of being, re-

sjicctively, in the material world. There are three

stages through which the mind passes in order to

secure a total view of the world of which it is spec-

tator. The Middle Ages defines physics, or the

philosophy of nature, as "the study of the material

world in so far as it is carried in the stream of

change, motiis." Change! Whether, indeed, it is

a question of the inorganic kingdom or of the realm

of the living, of plants or of human life, of the

16= Thomas Aquinas, In Metaph. I, lect. 2. "Sapientia est scientia

quae considerat primas et unlversales causas."

92 PHILOSOPHY AND CIVILIZATION

atom or of the course of the stars : all that is in the

sensible world, becomes ^ that is to say, changes,

evolves; or, to use the expression of the Middle

Ages, everything is in motion (movere). To

study, in its inmost nature, change and its implica-

tions, in order to explain the movements of the ma-

terial world, — this is the task of the philosophy of

nature/^ It is easy to see that this study is of a

regressive and synthetic kind, that it is general,

that is to say, philosophical, on account of the gen-

eral character of the material investigated (ma-

terial object), and the generality of the point of

view from which the inquiry is undertaken ( formal

object). But through all their changes and trans-

formations bodies preserve a common attribute, the

primary attribute of body — quantity — so that the

study of quantity forces us to penetrate reality still

further. Mathematics, which studies quantity as

regards its logical implications, was for the ancients

a philosophical and therefore a general science, and

in our day many scientists are tending to return to

this Aristotelian notion. Metaphysics enters deep-

est of all into reality and deals with what is beyond

motion and quantity,— for the sole purpose of con-

sidering the general determinations of being.

But practical philosophy is no less general in

character, although it is not concerned with the uni-

versal order in its objective reality, but with the

17 Be it observed that, since man is a part of the world of sense-

perception, psychology also belongs to physics.