and this is a sound distinction. The distinction between what is in the mind and what is outside it is established, known, and beyond doubt. To posit a reality that is established neither in knowledge nor in existence, however, is invalid.

The “second principle”—the distinction between what necessarily accompanies an essence and what is essential to it—has no basis in reality. For if an essence outside the mind is taken to be stripped of its inseparable attributes, then existence outside the mind can likewise be taken to be stripped of these inseparable attributes. If, on the other hand, this is taken to be the essence itself together with its inseparable attributes, that is equivalent to saying: this is “existence together with its inseparable attributes.” Both are invalid. Evenness and oddness in a number, for example, are like being an animal and being rational in a human being. In either case, when the subject is brought to mind together with its attribute, the subject cannot be conceived without that attribute.

Their claim that what they classify as essential takes precedence in its mental representation is invalid on two grounds:

(The first is that this merely describes their own convention: they place one thing first in their minds and another later. This is nothing more than a judgment on their part. Anyone who gives this precedence over that is merely following them in doing so. It is well known that external realities, which are independent of us, do not depend on our conceptions. Our supposing one thing to come first and another later does not make them so outside the mind. Other people who follow them on this point do not have this precedence in mind