The Six Books of Proclus on the Theology of Plato, Volume 2

For if it gives existence, and makes the communication from its own essence, that which it gives is subordinate to its own essence [by the 7th Proposition]. But that which it is, it is in a greater and more perfect degree; since every thing which gives subsistence to a certain thing, is better than and not the same with it. For it is primarily, but the other is secondarily that which it is. For it is necessary either that each should be the same, and that there should be one definition of both, or that there should be nothing common and the same in both, or that the one should subsist primarily, but the other secondarily. If however indeed, there is the same definition of both, the one will no longer be cause, but the other effect; nor will the one subsist essentially, but the other by participation; nor will the one be the maker, but the other the thing made. But if they have nothing which is the same, the one will not give subsistence to the other by its very being, in consequence of communicating nothing to the existence of the other. Hence, it remains that the one should be primarily that which it gives, but that the other should be secondarily that to which existence is given; the former supplying the latter from its very being.