Consider the following argument:

1. If it’s possible for a thing to come into existence without a cause, this possibility is grounded in a property of the thing itself, or a property of nothingness.
2. This possibility is not grounded in a property of the thing itself, nor in a property of nothingness.
3. Therefore, it is not possible for a thing to come into existence without a cause.

That possibilities are grounded in properties of things seems quite intuitive. In (1), we exclude the option of there being a property of an external thing that grounds this possibility, for it’s difficult to see how that would be a case of something coming into existence without a cause. (2) follows from the fact that only things that exist can exemplify properties. Nothingness, since it is the absence of all being, therefore doesn’t have any properties. Nor does the thing itself exemplify any properties prior to its existing.