Nuprl Definition : TI
TI is the principle of "transfinite induction" for the
given relation R on type T.
Unfortunately, it is well-formed only when Q[t] is a proposition
on type T, so it can't be used to prove that some Q' is a proposition.⋅
TI(T;x,y.R[x; y];t.Q[t]) == (∀t:T. ((∀s:{s:T| R[t; s]} . Q[s])
⇒ Q[t]))
⇒ (∀t:T. Q[t])
Definitions occuring in Statement :
all: ∀x:A. B[x]
,
implies: P
⇒ Q
,
set: {x:A| B[x]}
Definitions occuring in definition :
implies: P
⇒ Q
,
set: {x:A| B[x]}
,
all: ∀x:A. B[x]
FDL editor aliases :
TI
Latex:
TI(T;x,y.R[x; y];t.Q[t]) == (\mforall{}t:T. ((\mforall{}s:\{s:T| R[t; s]\} . Q[s]) {}\mRightarrow{} Q[t])) {}\mRightarrow{} (\mforall{}t:T. Q[t])
Date html generated:
2016_07_08-PM-04_47_11
Last ObjectModification:
2015_09_22-PM-05_45_19
Theory : bar-induction
Home
Index