3. Complex ideas are voluntary combinations.
Though the mind be wholly passive in respect of its simple ideas;
yet, I think, we may say it is not so in respect of its complex ideas. For those being combinations of simple ideas
put together, and united under one general name, it is plain that the mind of man uses some kind of liberty in
forming those complex ideas: how else comes it to pass that one man's idea of gold, or justice, is different from
another's, but because he has put in, or left out of his, some simple idea which the other has not? The question
then is, Which of these are real, and which barely imaginary combinations? What collections agree to the reality
of things, and what not? And to this I say that,
