subsection‹HC, SC, and ND› theory HCSCND imports HCSC SCND NDHC begin theorem HCSCND: defines "hc F ≡ AX10 ⊢⇩H F" defines "nd F ≡ {} ⊢ F" defines "sc F ≡ {#} ⇒ {# F #}" shows "hc F ⟷ nd F" and "nd F ⟷ sc F" and "sc F ⟷ hc F" using HCSC[where F=F and Γ=‹{#}›, simplified] SCND[where Γ=‹{#}› and Δ="{#F#}"] ND.ND.CC[where F=F and Γ="{}"] NDHC[where Γ="{}" and F=F] by(simp_all add: assms) blast+ end