In the preceding discussion of existential import, it was shown why, in the Boolean interpretation of propositions adopted in this book, most of the inferences that traditionally were thought to be valid are not valid. These inferences mistakenly assume that certain classes have members, thereby committing the existential fallacy. This fallacy is committed in each of the arguments presented below. Explain the point or points at which, in each argument, the mistaken existential assumption is made.

(1) It is true that: No unicorns are animals found in the Bronx Zoo; therefore, 

(2) It is false that: All unicorns are animals found in the Bronx Zoo; therefore 

(3) It is true that: Some unicorns are not animals found in the Bronx Zoo. 

(From which it follows that there exists at least one unicorn.)