The research of Dr. Fred Luskin of Stanford University, and author of the book "Forgive for Good" presented evidence that forgiveness can be learned (i.e. can be a teachable skill, with practice) based on research projects into the effects of teaching forgiveness: giving empirical validity to the concept that forgiveness is powerful as well as excellent for your health. In three separate studies, including one with Catholics and Protestants from Northern Ireland whose family members were murdered in the political violence, he found that people who are taught how to forgive become less angry, feel less hurt, are more optimistic, become more forgiving in a variety of situations, and become more compassionate and self-confident. His studies show a reduction in experience of stress, physical manifestations of stress, and an increase in vitality.