Open Lev135 opened 2 years ago
Yes, that's not supported at the moment. Do you have a reference to standard tableau rules for a language with top and bottom? Any branch with bottom or ~top is closed?
@wo Yes, from Fitting 2007 (Handbook of Modal logic, chapter 2): "A tableau branch is called closed if it contains T Z and F Z for some formula Z, or if it contains F \top, or T \botom. A tableau is closed if every branch is closed."
As I can see, there is no way to enter logical constants (I've tried
top
/bottom
/0
/1
). Of couse, one can usep -> p
for top, but it isn't convenient. Although constants are not very usefull in classical logic, they often occur in modal logic formulas.