The rigour of science requires that we distinguish well the undraped figure of Nature itself from the gay-coloured vesture with which we clothe her at our pleasure.
as quoted by Ludwig Boltzmann in a letter to Nature (February 28, 1895).
It is not particularly satisfactory to see equations set forth as direct results of observation and experiment, where we used to get long mathematical deductions as apparent proofs of them. Nevertheless, I believe that we cannot, without deceiving ourselves, extract much more from known facts than is asserted in the papers referred to. If we wish to lend more color to the theory, there is nothing to prevent us from supplementing all this and aiding our powers of imagination by concrete representations of the various conceptions as to the nature of electric polarisation, the electric current, etc.Heinrich Hertz