I do. Because oftentimes eyes cannot disguise your true feelings unless you're a good actor. Looking carefully at the person's eyes can even tell you whether he is really interested in what you are talking about or not. You can see that in the size of the pupils. If they're small than he's just pretending, but if they're enlarged, then he is all with you. It has been proved that the muscle responsible for the size of pupils cannot be consciously controlled, so your saying has even been scientifically proved. :)
Because if a person is saying something and they're lying they immediately look up to the right. Why? Because that's where their right brain is. The creative side that can think of a good story. If they're telling the truth they'll look to the left. Their logical side.