OCKHAM RAZOR

One of the most famous scientific endorsements of Ockham’s Razor can be found in Isaac Newton’s Mathematical Principles of Natural Philosophy (1687), where he states four ‘Rules of Reasoning’. Here are the first two:

Rule I. No more causes of natural things should be admitted than are both true and sufficient to explain their phenomena. As the philosophers say: nature does nothing in vain, and more causes are in vain when fewer suffice. For nature is simple and does not indulge in the luxury of superfluous causes.

Rule II. Therefore, the causes assigned to natural effects of the same kind must be, so far as possible, the same. Examples are the cause of respiration in man and beast, or of the falling of stones in Europe and America, or of the light of a kitchen fire and the Sun, or of the reflection of light on our Earth and the planets