Every A is X Every B is X │Some A is X Some B is X Every X is B Every X is A │No X is B No X is A ———————————— ———————————— │———————————————— ———————————————— Every A is B Every B is A │Some A is not B Some B is not A │ Every A is X Every B is X │Every A is X Every B is X No X is B No X is A │Some B is not X Some A is not X ———————————— ———————————— │———————————————— ———————————————— No A is B No B is A │Some B is not A Some A is not B │ Some A is X Some B is X │Every X is A Every X is B Every X is B Every X is A │Some X is not B Some X is not A ———————————— ———————————— │———————————————— ———————————————— Some A is B Some B is A │Some A is not B Some B is not A In the list of page 19, there was nothing but recapitulation of forms, each form admitting a variation by interchanging A and B. This interchange having been made, and the results collected as above, if we take every case in which B is the predicate, or can be made the predicate by allowable conversion, we have a collection of all possible _weakest_ forms in which the result is one of the four ‘Every A is B,’ ‘No A is B,’ ‘Some A is B,’ ‘Some A is not B’; as follows. The premises are written in what appeared the most natural order, without distinction of major or minor; and the letters prefixed are according to the forms of the several premises, as in page 10. A Every A is X U Every X is B ———————————— A Every A is B I Some A is X I Some B is X U Every X is B U Every X is A ———————————— ———————————— I Some A is B I Some A is B A Every A is X A Every B is X E No B is X E No A is X ———————————— ———————————— E No A is B E No A is B I Some A is X A Every B is X U Every X is A E No B is X O Some A is not X Y Some X is not B ———————————————— ———————————————— ———————————————— O Some A is not B O Some A is not B O Some A is not B