Full Idea
The smallest parts of matter are not the fundamental Beings, as in the philosophy of Democritus, but are mathematical forms. Here it is quite evident that the form is more important than the substance of which it is the form.
Gist of Idea
Basic particles have a mathematical form, which is more important than their substance
Source
Werner Heisenberg (Physics and Philosophy [1958], 04)
Book Reference
Heisenberg,Werner: 'Physics and Philosophy' [Penguin 1989], p.57
A Reaction
Heisenberg is quite consciously endorsing hylomorphism here, with a Pythagorean twist to it.