Nuprl Lemma : dl-diamond-choose

a,b:Prog. ∀phi:Prop.  (<a ⋃ b> phi ⇐⇒ <a> phi ∨ <b> phi)


Proof




Definitions occuring in Statement :  dl-equiv: (phi ⇐⇒ psi) dl-diamond: <x1> x dl-or: x1 ∨ x dl-choose: x1 ⋃ x dl-prop: Prop dl-prog: Prog all: x:A. B[x]
Definitions unfolded in proof :  all: x:A. B[x] dl-equiv: (phi ⇐⇒ psi) and: P ∧ Q dl-valid: |= phi dl-prop-sem: [|phi|] dl-sem: dl-sem(K;n.R[n];m.P[m]) uall: [x:A]. B[x] so_lambda: λ2x.t[x] member: t ∈ T top: Top so_apply: x[s] so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]) so_apply: x[s1;s2;s3;s4] so_lambda: λ2y.t[x; y] so_apply: x[s1;s2] dl-prog-sem: [|alpha|] implies:  Q exists: x:A. B[x] or: P ∨ Q cand: c∧ B subtype_rel: A ⊆B prop: guard: {T}
Lemmas referenced :  dl-ind-dl-implies istype-void dl-ind-dl-diamond dl-ind-dl-choose dl-ind-dl-or dl-prog-sem_wf istype-nat subtype_rel_self dl-prop-sem_wf istype-universe dl-prop_wf dl-prog_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation_alt independent_pairFormation sqequalRule cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin isect_memberEquality_alt voidElimination hypothesis productElimination unionElimination inlFormation_alt dependent_pairFormation_alt hypothesisEquality productIsType universeIsType applyEquality lambdaEquality_alt instantiate universeEquality because_Cache inhabitedIsType inrFormation_alt unionIsType functionIsType

Latex:
\mforall{}a,b:Prog.  \mforall{}phi:Prop.    (<a  \mcup{}  b>  phi  \mLeftarrow{}{}\mRightarrow{}  <a>  phi  \mvee{}  <b>  phi)



Date html generated: 2019_10_15-AM-11_44_38
Last ObjectModification: 2019_03_27-AM-00_29_32

Theory : dynamic!logic


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