III. That in order to demonstrate the existence of a necessary being, it is sufficient to know that something exists.
IV. We know by experience that something exists; for experience presents to us, if nothing else, the existence of our own thought.
[CHAPTER II.]
THE UNCONDITIONED.
12. The words, conditioned and unconditioned, are greatly used in modern philosophy; as the ideas which these terms express have a great analogy to those explained in the last chapter, I will briefly consider them here.
13. The conditioned is that which depends on a condition; that is to say, that which is supposed if another thing, which is called the condition, is supposed. If the sun is above the horizon, there is light; here the light is the conditioned, the sun the condition. The unconditioned is that which supposes no condition, as its name expresses.
14. The universe is an assemblage of conditioned beings; this is manifested by both internal and external experience: does any thing unconditioned exist? Yes.
15. Representing the universe by a series A, B, C, D, E, F, ... etc., the condition of F is in E; the condition of E in D; that of D in C; that of C in B, and so on successively. If there is nothing unconditioned this retrogression will extend to infinity, and we shall have an infinite series of conditioned terms.
To arrive at any term, for example, B, it will have been necessary to pass through the infinite conditions which precede it: the infinite series will have been exhausted: this is contradictory. And as what is said of B may be said of A, or of any other of the preceding or succeeding terms, it follows that they are all impossible: therefore the series is absurd.