Full Idea
As our ideas are perpetually varied, without any change in the supposed real things, it necessarily follows that they cannot all be true copies of them.
Clarification
'Ideas' here are perception experiences
Gist of Idea
Since our ideas vary when the real things are said to be unchanged, they cannot be true copies
Source
George Berkeley (Three Dialogues of Hylas and Philonous [1713], III p.239)
Book Reference
Berkeley,George: 'The Principles of Human Knowledge etc.', ed/tr. Warnock,G.J. [Fontana 1962], p.239
A Reaction
This seems a good objection to any direct or naïve realist view. Colours get darker as the sun goes down, and objects become blurred as they recede into the distance.