There is an interesting teaching in Patanjali’s Yoga Sutras in the book How to Know God that describes how one can benefit by observing ones reactions and how one can benefit from observing ones reactions to ones reactions.
A example would be to observe ones reactions when one experiences ones own prejudice to something or someone.
Let’s say one sees a person wearing flashy jewelry and driving an expensive car.
One might jump to the conclusion that the person is a drug dealer, whereas he might be a human rights lawyer and simply have a taste for flashy jewelry and expensive cars.
Let’s say you are white and he is black. You think for sure he must be a drug dealer, then you pull back and say ‘No, no, this is not my reaction – I dissociate myself from it. It is not me.’
In reality it is that I cannot bear to think that this is ‘me’, but of course if is ‘me’ and looking clearly at ‘me’ helps to step back behind ‘me’ and find what is there.