And validity is one of the trademarks of a good argument. But there are also some complications. Categorical statements must be expressed in the standard forms depicted above. Terms of a categorical statement must include a noun or pronoun that denotes a class. These restrictions may not always comport well with our ordinary language usage.
Terms can be complicated noun phrases.
This can make working with them a bit cumbersome. All philosophers who study such things as consciousness, folk psychology, and perception are philosophers of mind and psychology. For example, an adjective may appear without a noun or pronoun. All logicians are rational creatures. All fish swim.