"Normally we divide the external world into that which we consider to be good or valuable, bad or worthless, or neither. Most of the time these discriminations are incorrect or have little meaning. For example, our habitual way of categorizing people as friends, enemies, and strangers depending on how they make us feel is both incorrect and a great obstacle to developing impartial love for all living beings. Rather than holding so tightly to our discriminations of the external world, it would be much more beneficial if we learned to discriminate between valuable and worthless states of mind."