Werner Heisenberg

What happens depends on our way of observing it or on the fact that we observe it.

We have to remember that what we observe is not nature in itself but nature exposed to our method of questioning.
Werner Heisenberg - Philosophical Problems of Nuclear Science, New York: Fawcett 1966, p.13
A consistent pursuit of classical physics forces a transformation in the very heart of that physics.

- Werner Heisenberg