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C H A P T E R IX.

Containing Sir Isaac Newt ans rules of reasoning in philosophy, witha variety of experiments in eleBricity and magnetism, and also many

observations on the different operations of stature, which appear toprove the eleBric particles have a kind of polarity, or an attraBiveand repulsive property to each of them .

Rule I.

E are to admit no more causes of natural things than

such as are both true, and sufficient to explain their

appearances.

To this purpose the philosophers fay, that nature does no-thing in vain, and more is in vain when less will serve; fornature is pleased with simplicity, and affects not the pomp ofsuperfluous causes.

Rule II.

Therefore to the same natural effects we must, as far as pos-sible, assign the same causes.

As to respiration in a man and in a beast; the descent ofstones in Europe and America; the light of our culinary fireand of the fun; and the reflection of light in the earth and theplanets.

Rule III.

The qualities of bodies, which admit neither intension nor

io

' Motte’s Newton’s Principia, vol. ii. p. 202.

remission