diff --git a/docs/ghost-state.tex b/docs/ghost-state.tex index 8d15141405245ee9c6501c9b2338aa4b3bf05b53..2d259b3d372661d19dd79c5eab87ba6a741f0a3b 100644 --- a/docs/ghost-state.tex +++ b/docs/ghost-state.tex @@ -60,7 +60,13 @@ It turns out that we can somewhat mitigate this trouble by working below the fol This modality is useful because there is a class of propositions which we call \emph{timeless} propositions, for which we have \[ \timeless{\prop} \eqdef \later\prop \proves \diamond\prop \] -In other words, when working below the except-0 modality, we can \emph{strip away} the later from timeless propositions. +In other words, when working below the except-0 modality, we can \emph{strip + away} the later from timeless propositions. In fact, we can strip away later +from timeless propositions even when working under the later modality: +\begin{mathpar} + \infer{\prop \proves \later \propB} + {\later\prop \proves \later\propB} +\end{mathpar} The following rules can be derived about except-0: \begin{mathpar}