the proof of the pudding (is in the eating) in British English.
The windows to the soul. Your eyes communicate more than you may think -- and you canât always control everything they reveal. Body language experts tell how to read a personâs eyes to tell if theyâre happy to see you, disgusted, bored, stressed and even lying. Pupil size.
People cannot make eye contact when lying, so if someone does not look at your eyes straightly when talking to you, then you should know that they are lying to you. However, the views that liars cannot make eye contact are well-known so that people lying are very carefully to maintain good eye contact with the opposite.