Therefore we in vain pretend to range things into sorts, and dispose them into certain classes under names, by their real essences, that are so far from our discovery or comprehension.

A blind man may as soon sort things by their colours, and he that has lost his smell as well distinguish a lily and a rose by their odours, as by those internal constitutions which he knows not.

He that thinks he can distinguish sheep and goats by their real essences, that are unknown to him, may be pleased to try his skill in those species called CASSIOWARY and QUERECHINCHIO; and by their internal real essences determine the boundaries of those species, without knowing the complex idea of sensible qualities that each of those names stand for, in the countries where those animals are to be found.
10.

Not the substantial Form, which know Not.
Those, therefore, who have been taught that the several species of substances had their distinct internal SUBSTANTIAL FORMS, and that it was those FORMS which made the distinction of substances into their true species and genera, were led yet further out of the way by having their minds set upon fruitless inquiries after 'substantial forms'; wholly unintelligible, and whereof we have scarce so much as any obscure or confused conception in general.
11.

That the Nominal Essence is that only whereby we distinguish Species of Substances, further evident, from our ideas of finite Spirits and of God.
That our ranking and distinguishing natural substances into species consists in the nominal essences the mind makes, and not in the real essences to be found in the things themselves, is further evident from our ideas of spirits.