If a man will begin with certainties, he shall end in doubts; but if he will be content to begin with doubts, he shall end in certainties. - Francis Bacon

There are four classes of Idols which beset men's minds. To these for distinction's sake I have assigned names — calling the first class, Idols of the Tribe; the second, Idols of the Cave; the third, Idols of the Market-Place; the fourth, Idols of the Theater.

The human understanding when it has once adopted an opinion (either as being the received opinion or as being agreeable to itself) draws all things else to support and agree with it. And though there be a greater number and weight of instances to be found on the other side, yet these it either neglects and despises, or else by some distinction sets aside and rejects, in order that by this great and pernicious predetermination the authority of its former conclusions may remain inviolate.

To conclude, therefore, let no man upon a weak conceit of sobriety or an ill-applied moderation think or maintain that a man can search too far, or be too well studied in the book of God's word, or the book of God's works, divinity or philosophy; but rather let men endeavor an endless progress or proficience in both; only let men beware that they apply both to charity, and not to swelling; to use, and not to ostentation; and again, that they do not unwisely mingle or confound these learnings together.