27O Human Understanding, 



ledge. Thus we see that red is not green - 9 

 that the whole is bigger than a part ; that 

 two and two are equal to four. 



The truth of these and the like propo- 

 sitions we know by bare simple intuition 

 of the ideas themselves, without any more 

 ado ; and such propositions are called 

 self-evident. 



The mediate perception of the agree-, 

 ment or disagreement of two ideas, is, 

 when by the intervention of one or more 

 other ideas, their agreement or disagree- 

 ment is shewn. This is called Demon- 

 stration or Rational Knowledge. For 

 instance, the inequality of the breadth 

 of two windows, or two rivers, or any 

 two bodies that cannot be put together, 

 may be known by the intervention of 

 the same measure applied to them both ; 

 and so it is in our general ideas, whose 

 agreement or disagreement may be often 

 shewn by the intervention of some other 

 ideas, so as to produce demonstrative 

 knowledge, where the ideas in question 

 cannot be brought together, and immedi- 

 ately compared, so as to produce intui- 

 tive knowledge. 



Secondly, Of Judgment. 



