Joseph asked:

If somebody says: "I am now lying", is he telling the truth?

============

Or, you could say, on Wednesday: "I only tell lies on Wednesday." Then what? To answer your
question, that statement of course sets up a paradox which is irresolvable within that context. Now,
the question I have for you is, why have you asked that question above? Are you interested in
paradoxes generally; did you just want to confuse a "philosopher"; were you genuinely interested in
whether there is a way to resolve paradoxes of that sort? As to the last alternative, there is not. You
might look up the "Prisoner's Dilemma" for a really nasty problem of this sort.

Steven Ravett Brown