pattern ruled out    
relation φ ψ   relation
(entails) φ ⊨ ψ T F
φ ≃ ψ (equivalent)
(is entailed by) φ ⫤ ψ F T
(mutually exclusive) φ ▵ ψ T T
φ ⋈ ψ (contradictory)
(jointly exhaustive) φ ▿ ψ F F