All science is either physics or stamp collecting.

  • Ernest Rutherford, as quoted in Rutherford at Manchester(1962) by J. B. Birks
    • Unsourced variants:
    • That which is not measurable is not science. That which is not physics is stamp collecting.
    • Physics is the only real science. The rest are just stamp collecting.
    • That which is not measurable is not science. — (which is also attributed to Lord Kelvin)