_Aspice, quam mage sit nostrum penetrabile telum._ 7. _God is the first reason of things_: for such things as are bounded, as all that which we see and experience, are contingent and have nothing in them to render their existence necessary, it being plain that time, space and matter, united and uniform in themselves and indifferent to everything, might have received entirely other motions and shapes, and in another order. Therefore one must seek the reason for the existence of the world, which is the whole assemblage of _contingent_ things, and seek it in the substance which carries with it the reason for its existence, and which in consequence is _necessary_ and eternal. Moreover, this cause must be intelligent: for this existing world being contingent and an infinity of other worlds being equally possible, and holding, so to say, equal claim to existence with it, the cause of the world must needs have had regard or reference to all these possible worlds in order to fix upon one of them. This regard or relation of an existent substance to simple possibilities can be nothing other than the _understanding_ which has the ideas of them, while to fix upon one of them can be nothing other than the act of the _will_ which chooses. It is the _power_ of this substance that renders its will efficacious. Power relates to _being_, wisdom or understanding to _truth_, and will to _good_. And this intelligent cause ought to be infinite in all ways, and absolutely perfect in _power_, in _wisdom_ and in _goodness_, since it relates to all that which is possible. [128] Furthermore, since all is connected together, there is no ground for admitting more than _one_. Its understanding is the source of _essences_, and its will is the origin of _existences_. There in few words is the proof of one only God with his perfections, and through him of the origin of things.