substitution of terms

Anyone who thinks they can talk about quantum theory without feeling dizzy hasn't yet understood the first thing about it.
—Niels Bohr

Anyone who thinks they can talk about poetry without feeling dizzy hasn’t yet understood the first thing about it.

inside the atom

We must be clear that when it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images and establishing mental connections.

—Niels Bohr, in his first meeting with Werner Heisenberg in early summer 1920, quoted in Theorizing Modernism: Essays in Critical Theory (1993) by Steve Giles, p. 28.