What Can we Know?
LIMITATIONS OF KNOWLEDGE
All knowledge comes only through sense experience. The observer responds to qualities in the perceived object. The ideas he can develop about the object are limited by his powers of perception. In this empirical approach to knowledge, Locke directly opposed French rationalism (a tradition initiated by Descartes) with its emphasis on mind and reason. The implication of Lockešs "way of ideas" is that our knowledge is limited "to the paucity and imperfections of the ideas we have". There is no absolute knowledge. His conclusion: "But as to a perfect science ...we are, I think, so far from being capable of any such thing, that I conclude it lost labour to seek after it."
("Essay Concerning Human Understanding" Bk I, Ch 1)
STATUTE OF LIMITATIONS
Likewise, there is no absolute liberty. Locke's aim was ever to face the fact that there were always limits and to identify those limits. Having identified the systemic sources of limitations, no further limitations should be accepted. The limits of liberty are set by the nature of political societies, that is by the need to protect the life, property and freedom of individuals and defend all from common enemies. Once those limitations are recognised, no further limitations should be accepted.