the Stoics the Good is only a virtue, and virtue is a definite condition of that material which constitutes the soul. [263] In the same sense also truth is said to be material, personal and not independent, truth being of course meant, [264] that is to say, knowledge, or a property of the soul that knows. And since according to the Stoics knowledge consists in the presence of certain material elements within the soul, truth in the sense of knowledge may be rightly called something material. Even emotions, impulses, notions and judgments, in so far as they are due to material causes—the air-currents pouring into the soul (πνεύματα)—were regarded as material objects, and for the same reason not only artistic skill but individual actions were said to be corporeal. [265] Yet [(γ) The causes of actions material.] certain actions, such as walking and dancing, can hardly have been called bodies by the Stoics, any more than being wise was called a body; [266] but the objects which produced these actions, as indeed everything which makes itself felt, were considered to be corporeal. To us it appears most natural to refer these actions to the soul as their originating cause; but the Stoics, holding the theory of subject-matter and property, preferred to refer each such action to some special material as its cause, considering that an action is due to the presence of this material. The idealism of Plato was thus reproduced in a new form by the materialism of the Stoics. Plato had said, a man is just and musical when he participates in the idea of justice and music; the Stoics said, a man is virtuous when the material producing virtue is in him; musical, when he has the material producing music. [(δ) Wide extension of material.] Moreover, these materials produce the phenomena of life. Hence, not content with calling them bodies, the Stoics actually went so far as to call them living beings. It seems, however, strange to hear such things as day and night, and parts of the day and parts of the night, months and years, even days of the month and seasons of the year, called bodies; [267] but by these singularly unhappy expressions Chrysippus appears to have meant little more than that the realities corresponding to these names depend on certain material conditions: by summer is meant a certain state of the air when highly heated by the sun; by month the moon for a certain definite period during which it gives light to the earth. [268] From all these examples one thing is clear, how impossible the Stoics found it to assign reality to what is not material. [(b) The incorporeal or non-material.]