3p4d.md (393B)
1 This proposition is self–evident, for the definition 2 of anything affirms the essence of that thing, but does not 3 negative it; in other words, it postulates the essence of the 4 thing, but does not take it away. So long therefore as we regard 5 only the thing itself, without taking into account external 6 causes, we shall not be able to find in it anything which could 7 destroy it. Q.E.D. 8 9