An Essay Concerning Human Understanding

The founding text of classical British empiricism. The denial of innate ideas, the doctrine that all knowledge originates in experience, and the careful distinction between primary and secondary qualities all define the school.

"Let us then suppose the Mind to be, as we say, white Paper, void of all Characters, without any Ideas: How comes it to be furnished?... To this I answer, in one word, From Experience." (Essay II.1.2)

Locke's working metaphysics is realist about external objects and modest about how much we can know — a pragmatist temperament before the term existed. Book IV.3 carefully delimits what we can and cannot know.

"How short soever their knowledge may come of an universal or perfect comprehension of whatsoever is, it yet secures their great concernments." (Essay I.1.6)

Locke retains a robust realism about the external world and about substances (despite his careful agnosticism about their "real essences"); the primary-secondary quality distinction presupposes a mind-independent material order.

"The simple Ideas we receive from Sensation and Reflection are the boundaries of our thoughts." (Essay II.23.29)

Locke's representationalism — we perceive ideas, not objects directly — is the route Berkeley and Hume will follow further into phenomenalism. The Essay is the structural precursor.

"The Mind, in all its Thoughts and Reasonings, hath no other immediate Object but its own Ideas." (Essay IV.1.1)

Locke's natural theology — the existence of God is demonstrable by reason from the existence of thinking beings — is the eighteenth-century Anglophone deist programme in its most authoritative form. The Reasonableness of Christianity (1695) develops it.

"Thus from the Consideration of our selves, and what we infallibly find in our own Constitutions, our Reason leads us to the Knowledge of this certain and evident Truth, That there is an eternal, most powerful, and most knowing Being." (Essay IV.10.6)

Social-contract tradition.