Jean Baptiste Fourier...on mathematical analysis

Its chief attribute is its clarity. It has no symbols to express confused ideas. It brings together the most diverse phenomena and discovers hidden conformities which unite them. If matter evades us, such as the air and light, because of its extreme thinness, if objects are located far from us in the immensity of space, if man wishes to understand the performance of the heavens for the successive periods which separate a large number of centuries, if the forces of gravity and of heat be at work in the interior of a solid globe at depths which will be forever inaccessible, mathematical analysis can still grasp the laws of these phenomena. It renders them present and measurable, and seems to be a faculty of the human reason destined to make up for the brevity of life, and for the imperfection of the senses. And what is more remarkable still, it follows the same method in the study of all phenonema. It interprets man in the same language, in some measure to affirm the unity and simplicity of the plan of the universe, and to make still more manifest the immutable order which rules all natural matter.

Theorie analytique de la chaleur, 1822