A violation of the first rule would result in undistributed middle; whereas a violation of the second rule would give illicit major. These rules may be illustrated by giving attention to the symbols of the foregoing completed syllogisms.
The first completed syllogism of the sorites is:
All A is B
All B is C
∴ All A is C
Securing a logical arrangement by interchanging the major and minor premises gives:
(A) All (M)
B is (G)
C (First premise universal)
(A) All (S)
A is (M)
B
(A) ∴ All (S)
A is (G)
C
Applying the rules we find this syllogism valid, or we may recall that A
A
A is valid in the first figure.