Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.

It seems to me, that the only Objects of the abstract Sciences or of Demonstration is Quantity and Number, and that all Attempts to extend this more perfect Species of Knowledge beyond these Bounds are mere Sophistry and Illusion.

When we reflect on our past sentiments and affections, our thought is a faithful mirror, and copies its objects truly; but the colours which it employs are faint and dull, in comparison of those in which our original perceptions were clothed.

Mohammed praises [instances of] tretchery, inhumanity, cruelty, revenge, and bigotry that are utterly incompatible with civilized society.

This avidity alone, of acquiring goods and possessions for ourselves and our nearest friends, is insatiable, perpetual, universal, and directly destructive of society.

Upon the whole, necessity is something, that exists in the mind, not in objects; nor is it possible for us ever to form the most distant idea of it, consider'd as a quality in bodies. Either we have no idea of necessity, or necessity is nothing but that determination of thought to pass from cause to effects and effects to causes, according to their experienc'd union.

That the sun shines tomorrow is a judgement that is as true as the contrary judgement.