you may use one but don't mention it.

            At t₁, I come into existence and say nothing. At t₂ I say, “the cat is on mat” and nothing else. But, at t₂, the cat is not on the mat. At t₃, I say, “I never tell the truth” and nothing else.  What exactly am I saying? Here are some options:

(1)  What I said at t₂ is true.

(2)  What I said at t₂ is not true.

(3)  What I said at t₂ is true and what I am saying at t₃ is true.

(4)  What I said at t₂ is true and what I am saying at t₃ is not true.

(5)  What I said at t₂ is not true and what I am saying at t₃ is true.

(6)  What I said at t₂ is not true and what I am saying at t₃ is not true.

If (1), then what I say is false, full stop.

If (2), then what I say is true, full stop.

If (3), then what I say is false, full stop.

If (4), then what I say is false, full stop.

If (5), then what I say is true, full stop.

If (6), then what I say is false, full stop.

Are there any other options?  If not, whatever it is I say at t₃, it is not both true and false. Ergo, etc.