• The electron is a theory we use; it is so useful in understanding the way nature works that we can almost call it real.

    Richard P. Feynman: The electron is a theory we use; it is so useful in understanding the way nature works that we can almost call it real.
    "Surely You're Joking, Mr. Feynman!". Book by Richard P. Feynman, p. 70, 1985.