Certain personality tests and type systems have attracted popular attention in the past few decades. Some, like the Enneagram, are based on a centuries-old understanding of human types. Others, like the Myers-Briggs Type Indicator (MBTI), evolved from the work of Carl Jung, are more recent. Essentially, each system demonstrates just how different (but not special!) we are from each other. People see the world and respond to it from many perspectives. Our brain chemistries, our cultural environments, our childhood influences, our metabolisms - among dozens of factors - make us so unique that almost any culture's stereotypical generalizations about norms become highly questionable. Knowing this can also help us to gain compassion, both for ourselves and for others, as it reassures us that we don't have to fit in with one set of prevailing norms. Not meeting one set of standards doesn't mean there's something wrong with us.