If you tell a simple lie, there's not much work till you go, i don't know and you have nothing to say. We find that liars are often worried that if they are inconsistent, they will be thought to be lying. The thing is, learned, we really, you remember. And what we tend to do when people tell us lies, as i think, we fill in the blanks. It's sort of like comparing a litle photograph of your house with the tree in the front yard and a child's picture of it.