Hello,
from the hypothesis of INV1
I /\ [N]_f => I'
you can derive both
(1) [N]_f => [I => I']_f and (2) I /\ f'=f => I'
by propositional logic. Now, apply TLA1 to (1), with P and Q both TRUE, to derive
(3) [][N]_f => [][I => I']_f
(If you are really meticulous, use STL1 to get rid of the formula []TRUE on the left-hand side of the direct conclusion of TLA2.) From (2), TLA1 gives you
(4) []I <=> I /\ [][I => I']_f
and the conclusion of INV1 follows from (3) and (4).
Regards,
Stephan
> --
> You received this message because you are subscribed to the Google Groups "tlaplus" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to
tlaplus+u...@googlegroups.com.
> To view this discussion on the web visit
https://groups.google.com/d/msgid/tlaplus/73c9e238-d51f-4f38-b7dd-4137fe456fc9%40googlegroups.com.