When a right-handed person looks down and to their right, there is a very high correlation (although not 100 percent) with the emotion of sadness. The more time you spend around any given person in varying emotional states - so that you may "norm" them for this (and other) particular behavior(s) - the greater your accuracy. With left-handed people this will often (but not always) be mirrored to their Left Lower Quadrant - however, in general, the accuracy is less in left-handers. With some right-handed people, I've seen this to be in excess of 99+ % accurate, although with others it will be less so. Always look for other subtle signs of sadness as well. If three or more signs are present and congruent - their words may be positive, but their heart will be sad. Take heed.