I have repeatedly, and uniformly, expressly defined what a "lie" is. It is anything that someone, in any human natural language, will call a "lie". That verbal behavior is well defined and can be observed directly, without ambiguity. It is a common error for people to think their natural language computations are not succeptible to study.

Unless, of course, you want to argue that nobody has ever called anything a "lie." I would say that is a lie and am interested in how your brain computed that sentential episode in your brain. We know the answer to this question in much more detail than you might imagine based on what we know in computational cognitive neuroscience today.