"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? Whence has it all the materials of reason and knowledge?
To this I answer, in one word, from experience.... Our observation, employed either about
external sensible objects or about the internal operations of our minds perceived and reflected on
by ourselves, is that which supplies our understanding with all the materials of thinking."
John Locke, "Essay Concerning Human Understanding"
What ideas about knowledge does Locke express in this passage?