Nuprl Lemma : psub-same
∀a:formula(). (a ⊆ a ⇐⇒ True)
Proof
Definitions occuring in Statement : 
psub: a ⊆ b, 
formula: formula(), 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
true: True
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
implies: P ⇒ Q, 
true: True, 
member: t ∈ T, 
prop: ℙ, 
uall: ∀[x:A]. B[x], 
rev_implies: P ⇐ Q, 
uimplies: b supposing a
Lemmas referenced : 
psub_wf, 
true_wf, 
formula_wf, 
psub_weakening
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
independent_pairFormation, 
natural_numberEquality, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
because_Cache, 
dependent_functionElimination, 
independent_isectElimination
Latex:
\mforall{}a:formula().  (a  \msubseteq{}  a  \mLeftarrow{}{}\mRightarrow{}  True)
 Date html generated: 
2016_05_15-PM-07_13_42
 Last ObjectModification: 
2015_12_27-AM-11_30_34
Theory : general
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