Eight moral virtues that have figured prominently in various cultures throughout history will be discussed: altruism, empathy, gratitude, humility, and the “cardinal virtues” of justice, prudence, fortitude, and temperance. The focus will be on how to understand them and what their relationship is to happiness. It will be argued that all eight essential moral virtues enhance happiness in most people most of the time. Their favourable impact on happiness may motivate humans to become better, which includes the decision to subject (...) themselves voluntarily to moral bioenhancement (MBE)—in order to achieve this betterment. Nonetheless, the development of MBE technologies is still in its infancy and moral education remains the primary means for the moral enhancement of humans, as well as for the enhancement of their happiness. This may however change in the relatively near future. (shrink)