The quantum world is a world of waves, not particles. So we have to think of electron waves and proton waves and so on. Matter is 'incoherent' when all its waves have a different wavelength, implying a different momentum. On the other hand, if you take a pure quantum system – the electrons in a superconducting magnet, or the atoms in a laser – they are all in phase with one another, and they demonstrate the wave nature of matter on a large scale. Then you can see quite visibly what matter is down at its heart.

"An Interview with Carver Mead", American Spectator, Sep/Oct2001, Vol. 34 Issue 7, p68.