Nuprl Lemma : sq_or_functionality_wrt_iff

[P1,P2,Q1,Q2:ℙ].  ({P1 ⇐⇒ P2}  {Q1 ⇐⇒ Q2}  {P1 ↓∨ Q1 ⇐⇒ P2 ↓∨ Q2})


Proof




Definitions occuring in Statement :  sq_or: a ↓∨ b uall: [x:A]. B[x] prop: guard: {T} iff: ⇐⇒ Q implies:  Q
Definitions unfolded in proof :  guard: {T} sq_or: a ↓∨ b uall: [x:A]. B[x] member: t ∈ T implies:  Q iff: ⇐⇒ Q and: P ∧ Q squash: T or: P ∨ Q prop: rev_implies:  Q
Lemmas referenced :  iff_wf or_wf squash_wf
Rules used in proof :  sqequalSubstitution sqequalRule sqequalReflexivity sqequalTransitivity computationStep isect_memberFormation introduction cut lambdaFormation sqequalHypSubstitution productElimination thin independent_pairFormation imageElimination unionElimination independent_functionElimination hypothesis inlFormation hypothesisEquality imageMemberEquality baseClosed inrFormation lemma_by_obid isectElimination lambdaEquality dependent_functionElimination independent_pairEquality universeEquality isect_memberEquality because_Cache

Latex:
\mforall{}[P1,P2,Q1,Q2:\mBbbP{}].    (\{P1  \mLeftarrow{}{}\mRightarrow{}  P2\}  {}\mRightarrow{}  \{Q1  \mLeftarrow{}{}\mRightarrow{}  Q2\}  {}\mRightarrow{}  \{P1  \mdownarrow{}\mvee{}  Q1  \mLeftarrow{}{}\mRightarrow{}  P2  \mdownarrow{}\mvee{}  Q2\})



Date html generated: 2016_05_13-PM-03_13_28
Last ObjectModification: 2016_01_06-PM-05_48_08

Theory : core_2


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