It's not about disregarding that external factors can and do significantly interfere with anyone's life. It's about recognizing that the most significant contri

It's not about disregarding that external factors can and do significantly interfere with anyone's life. It's about recognizing that the most significant contribution to your well being is in fact your own actions in the vast majority of cases and especially on longer time scales. It makes no sense to worry about the external factors that affect an individuals life since there is no way to affect those to a significant degree.