*While the standard form "No S is P" is unambiguous, the form "All S is not P" is ambiguous[REF] and so is not a standard form: because it can be either an E or O proposition, it requires a context to determine the form.
Aristotle states (in chapters six and seven of the Peri hermaneias (Περὶ Ἑρμηνείας, Latin De Interpretatione, English 'On Interpretation')), that there are certain logical relationships between these four kinds of proposition.