Were it only so

[keith evans - plant morphology - drawing on homemade paper - 1999 - via the art of memory]

Democritus believes that the nature of the eternal things is small beings unlimited in multitude. [...] He holds that the substances are so small that they escape our senses. They have all kinds of forms and shapes and differences in size. Out of these as elements he generates and combines visible and perceptible bodies.
contend with one another and move in the void on account of their dissimilarity and the other differences I have mentioned, and as they move they strike against one another and become entangled in a way that makes them be in contact and close to one another, but it does not make any thing out of them that is truly one, for it is quite foolish that two or more things could ever come to be one.

The grounds he gives for why the substances stay together up to a point are that the bodies fit together and hold each other fast. For some of them are rough, some are hooked, others concave and others convex, while yet others have innumerable other differences. So he thinks that they cling to each other and stay together until some stronger necessity comes along from the environment and shakes them and scatters them apart.

[Aristotle, On Democritus, quoted by Simplicius, Commentary on Aristotle's On the Heavens]

He makes sweet that which is round and good-sized; astringent that which is large, rough, polygonal, and not rounded; sharp tasting, as its name indicates, that which is sharp in body, and angular, bent and not rounded; pungent that which is round and small and angular and bent; salty that which is angular and good-sized and crooked and equal sided; bitter that which is round and smooth, crooked and small sized; oily that which is fine and round and small.

[Theophrastus, Causes of Plants, referring to Democritus]