Hi all, I have two questions about resolution principle in math
logic theory. I know, how to arrange formulas for the resolution
method (CNF, Skolem...) but I don't know two things during
resolution process. 1) Can I repeatedly use the same clause? For
example: I will make resolution with clauses 1 and 2. I write
the resolvent to the end of the list. Can I use the same
variables or predicates of the 1st clause again for another
resolution?  2) Is there any rule that I have to use all basic
clauses for resolution or I can stop just in the moment I find
the empty resolvent? For explanation - theoretically - If I have
5 initial clauses in the list and I find empty resolvent during
first resolution. Is it OK or I have to continue and try all
remaining clauses?  Thank you in advance for the answer. Sorry
for my English...