Home | Texts by category | | Quick Search:   
Works by Aristotle
Pages of On The Heavens

Previous | Next

On The Heavens   

hexagon, and only two solids, the pyramid and the cube. But the theory

needs more than these because the elements which it recognizes are

more in number. Secondly, it is manifest that the simple bodies are

often given a shape by the place in which they are included,

particularly water and air. In such a case the shape of the element

cannot persist; for, if it did, the contained mass would not be in

continuous contact with the containing body; while, if its shape is

changed, it will cease to be water, since the distinctive quality is

shape. Clearly, then, their shapes are not fixed. Indeed, nature

itself seems to offer corroboration of this theoretical conclusion.

Just as in other cases the substratum must be formless and

unshapen-for thus the 'all-receptive', as we read in the Timaeus, will

be best for modelling-so the elements should be conceived as a

material for composite things; and that is why they can put off

their qualitative distinctions and pass into one another. Further, how

can they account for the generation of flesh and bone or any other

continuous body? The elements alone cannot produce them because

their collocation cannot produce a continuum. Nor can the

composition of planes; for this produces the elements themselves,

not bodies made up of them. Any one then who insists upon an exact

statement of this kind of theory, instead of assenting after a passing

glance at it, will see that it removes generation from the world.

Further, the very properties, powers, and motions, to which they

paid particular attention in allotting shapes, show the shapes not

to be in accord with the bodies. Because fire is mobile and productive

of heat and combustion, some made it a sphere, others a pyramid. These

shapes, they thought, were the most mobile because they offer the

fewest points of contact and are the least stable of any; they were

also the most apt to produce warmth and combustion, because the one is

angular throughout while the other has the most acute angles, and

the angles, they say, produce warmth and combustion. Now, in the first

place, with regard to movement both are in error. These may be the

Previous | Next
Site Search