In: Other
Write out of the syllogistic forms AEE -1, using S and P as the subject and predicate terms of the conclusion, and M as the middle term. Then test the validity of each syllogistic form using a Venn diagram.
We are told that this syllogism is in the first figure, and therefore the middle term, M, is the subject term of the major premise and the predicate term of the minor premise. The conclusion of the syllogism is an E proposition and therefore reads: No S is P. The first (major) premise (which contains the predicate term of the conclusion) is an A proposition, and therefore reads: All M is P. The second (minor) premise (which contains the subject term of the conclusion) is an E proposition and therefore reads: No S is M. This syllogism therefore reads as follows:
Tested by means of a Venn diagram, as in Figure 10, this syllogism is shown to be invalid, it is reflected in the diagram that there is an S which is P that is not shaded, and this contradicts the conclusion that no S is P.
All M is P. No S is M. Therefore, no S is P.