All knowledge degenerates into probability.

Enthusiasm, being the infirmity of bold and ambitious tempers, is naturally accompanied with a spirit of liberty; as superstition,on the contrary, renders men tame and abject, and fits them for slavery.

The whole of natural theologyresolves itself into one simple, though somewhat ambiguous proposition, That the cause or causesof order in the universe probably bear some remote analogy to human intelligence.

It is... a just political maxim, that every man must be supposed a knave.

Your corn is ripe today, mine will be so tomorrow. 'Tis profitable for us both that I should labor with you today, and that you should aid me tomorrow. I have no kindness for you, and know you have as little for me. I will not, therefore, take any pains upon your account . . . Here then I leave you to labor alone; you treat me in the same manner. The seasons change, and both of us lose our harvests for want of mutual confidence and security.

A CAUSE is an object precedent and contiguous to another, and so united with it that the idea of the one determines the mind to form the idea of the other, and the impression of the one to form a more lively idea of the other.

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.