The fourth dimension

24 THE FOURTH DIMENSION

the cause he advocates. It is as if from his firm foothold of being he could play with the thoughts under the burden of which others laboured, for from him springs that fluency of supposition and hypothesis which forms the texture of Plato’s dialectic.

Can the mind conceive a more delightful intellectual picture than that of Parmenides, pointing to the one, the true, the unchanging, and yet on the other hand ready to discuss all manner of false opinion, forming a cosmogony too, false “ but mine own” after the fashion of the time?

In support of the true opinion he proceeded by the negative way of showing the self-contradictions in the ideas of change and motion. It is doubtful if his criticism, save in minor points, has ever been successfully refuted. To express his doctrine in the ponderous modern way we must make the statement that motion is phenomenal, not real.

Let us represent his doctrine.

Imagine a sheet of still water into which a slanting stick

4 is being lowered with a motion verti-

cally downwards. Let 1, 2, 3 (Fig. 13),

2 he three consecutive positions of the

gz stick. A, B,C, will be three consecutive

positions of the meeting of the stick,

A with the surface of the water. As

the stick passes down, the meeting will move from A on to B and ¢,

Suppose now all the water to be removed except a film. At the meeting of the film and the stick there will be an interruption of the film. If we suppose the film to have a property, like that of a soap bubble, of closing up round any penetrating object, then as the stick goes vertically downwards the interruption in the film will move on.

Fig. 13.