Suppose all 20 students in a class can write. Writers include students, teachers, and many others. So we can infer that some writers are students, but not that every writer is a student. A predicate may cover a larger class than the original subject, forcing the converted proposition to become particular.
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Why every becomes some
Simple Conversion of Propositions: Definition, Method and Rules
Suppose all 20 students in a class can write. Writers include students, teachers, and many others. So we can infer that some writers are students, but not that every writer is a student. A predicate may cover a larger class than the original subject, forcing the converted proposition to become particular.