Single Idea 3935

[catalogued under 12. Knowledge Sources / B. Perception / 2. Qualities in Perception / e. Primary/secondary critique]

Full Idea

As we approach to or recede from an object, the visible extension varies, being at one distance ten or a hundred times greater than at another; doth it not follow that it is not really inherent in the object?


'Visible extension' is the apparent size. 'Small cows distant, big cows close'.

Gist of Idea

The apparent size of an object varies with its distance away, so that can't be a property of the object


George Berkeley (Three Dialogues of Hylas and Philonous [1713], I p.171)

Book Reference

Berkeley,George: 'The Principles of Human Knowledge etc.', ed/tr. Warnock,G.J. [Fontana 1962], p.171

A Reaction

Berkeley is confused, because he is too literally empirical. Qualities are not self-evidently primary or secondary, but are judged so after comparisons (e.g. with testimony, or with the other senses).