[2] Examples of the exact sciences are mathematics, optics, astronomy,[3] and physics, which many philosophers from Descartes, Leibniz, and Kant to the logical positivists took as paradigms of rational and objective knowledge.
[7][8] Given their ties to mathematics, the exact sciences are characterized by accurate quantitative expression, precise predictions and/or rigorous methods of testing hypotheses involving quantifiable predictions and measurements.
[13] This distinction was widely, but not universally, accepted until the scientific revolution of the 17th century.
[14] Edward Grant has proposed that a fundamental change leading to the new sciences was the unification of the exact sciences and physics by Kepler, Newton, and others, which resulted in a quantitative investigation of the physical causes of natural phenomena.
[15] Linguistics and comparative philology have also been considered exact sciences, most notably by Benjamin Whorf.