Skip to main content

Affirming a Disjunct

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

p or q; p; therefore not-q. Invalid.

Show

He's a veteran or a teacher. He's a veteran. "So he's not a teacher" — inclusive or: he may be both.

Watch for

DS's evil twin. It secretly upgrades ∨ to exclusive-or without paying for it.

Builds on

Unlocks

  • Nothing yet depends on this.