Description: Extend wff definition to include "all some" applied to a top-level implication, which means ps is true whenever ph is true, and there is at least one x where ph is true. (Contributed by David A. Wheeler, 20-Oct-2018) (Revised by David A. Wheeler, 12-Jul-2026)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | wals | wff AE x ( ph -> ps ) |