Every man carries about him a touchstone, if he will make use of it, to distinguish substantial gold from superficial glitterings, truth from appearances. And indeed the use and benefit of this touchstone, which is natural reason, is spoiled and lost only by assuming prejudices, overweening presumption, and narrowing our minds.
John LockeBrutes abstract not. -- If it may be doubted, whether beasts compound and enlarge their ideas, that way, to any degree; this, I think, I may be positive in, that the power of abstracting is not at all in them; and that the having of general ideas is that which puts a perfect distinction betwixt man and brutes, and is an excellency which the faculties of brutes do by no means attain to.
John LockeHence it is a mistake to think, that the supreme or legislative power of any common-wealth, can do what it will, and dispose of the estates of the subject arbitrarily, or take any part of them at pleasure.
John LockeReason, if consulted with, would advise, that their children's time should be spent in acquiring what might be useful to them when they come to be men, rather than to have their heads stuff'd with a deal of trash, a great part whereof they usually never do ('tis certain they never need to) think on again as long as they live: and so much of it as does stick by them they are only the worse for.
John Locke