Fourthly, That relation being the considering of one thing with another which is extrinsical to it, it is evident that all words that necessarily lead the mind to any other ideas than are supposed really to exist in that thing to which the words are applied are relative words: v.g.a MAN, BLACK, MERRY, THOUGHTFUL, THIRSTY, ANGRY, EXTENDED; these and the like are all absolute, because they neither signify nor intimate anything but what does or is supposed really to exist in the man thus denominated; but FATHER, BROTHER, KING, HUSBAND, BLACKER, MERRIER, &c., are words which, together with the thing they denominate, imply also something else separate and exterior to the existence of that thing. 11. All relatives made up of simple ideas. Having laid down these premises concerning relation in general, I shall now proceed to show, in some instances, how all the ideas we have of relation are made up, as the others are, only of simple ideas; and that they all, how refined or remote from sense soever they seem, terminate at last in simple ideas. I shall begin with the most comprehensive relation, wherein all things that do, or can exist, are concerned, and that is the relation of CAUSE and EFFECT: the idea whereof, how derived from the two fountains of all our knowledge, sensation and reflection, I shall in the next place consider. CHAPTER XXVI. OF CAUSE AND EFFECT, AND OTHER RELATIONS. 1. Whence the Ideas of cause and effect got. In the notice that our senses take of the constant vicissitude of things, we cannot but observe that several particular, both qualities and substances, begin to exist; and that they receive this their existence from the due application and operation of some other being. From this observation we get our ideas of CAUSE and EFFECT. THAT WHICH PRODUCES ANY SIMPLE OR COMPLEX IDEA we denote by the general name, CAUSE, and THAT WHICH IS PRODUCED, EFFECT. Thus, finding that in that substance which we call wax, fluidity, which is a simple idea that was not in it before, is constantly produced by the application of a certain degree of heat we call the simple idea of heat, in relation to fluidity in wax, the cause of it, and fluidity the effect. So also, finding that the substance, wood, which is a certain collection of simple ideas so called, by the application of fire, is turned into another substance, called ashes; i. e., another complex idea, consisting of a collection of simple ideas, quite different from that complex idea which we call wood; we consider fire, in relation to ashes, as cause, and the ashes, as effect. So that whatever is considered by us to conduce or operate to the producing any particular simple idea, or collection of simple ideas, whether substance or mode, which did not before exist, hath thereby in our minds the relation of a cause, and so is denominated by us. 2. Creation Generation, making Alteration.