Applied to practice, it [mathematics] becomes an art, like RHETORIC. In both these arts the form is everything, the substance nothing. To mathematics it is indifferent whether it reckons pence or pounds; to RHETORIC, whether it defends truth or falsehood.

In: John Stuart Blackie, The Wisdom of Goethe, Philosophy, Metaphysics, Logic, Truth and Science (pp. 170-171), William Blackwood & Sons. Edinburgh, Scotland. 1883