PTTP is in a single source file, so there is no special installation
procedure--just compile and load it; "consulting" the file in Prolog
should suffice.


to use PTTP,
1. compile and load pttp.pl into Prolog
2. use the 'pttp' predicate to compile formulas
3. use the 'prove' predicate to do a proof


for example,
pl
['pttp.pl'].
pttp((a(1),
      (not_a(X) ; b(X)))).
prove(b(Y)).