Full Idea
Let us suppose the mind to be, as we say, white paper, void of all characters, without any ideas.
Clarification
'Characters' are writing
Gist of Idea
The mind is white paper, with no writing, or ideas
Source
John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 2.01.02)
Book Reference
Locke,John: 'Essay Concerning Human Understanding', ed/tr. Nidditch,P.H. [OUP 1979], p.104
A Reaction
This is normally referred to as Locke's 'tabula rasa' idea, and is his denial of the existence of innate ideas. It is generally thought to be absurd, but note that he only 'supposes' it, presumably as a theoretical strategy, to investigate empiricism.