Among rare neurological disorders, the "pseudobulbar affect" is manifested by uncontrolled laughter or crying. It can be treated effectively in many cases with a combination of the drugs dextromethorphan and quinidine. But there is another malady for which the Food and Drug Administration has no cure, and that is the habit of affecting emotions insincerely in order to manipulate others. There is the habitual backslapper who uses laughter to avoid serious conversation, often out of insecurity. There is also the weeper whose tears flow to elicit sympathy.
A remarkable quality usually taken for granted, is that humans can laugh and cry unlike other creatures. "Risibility," the ability to laugh or smile, is a defining trait of humanity. The moral challenge is to identify the right causes of happiness and sadness.
All sane, moral behavior has the pursuit of happiness as the goal of life. Sadness is the recognition of what impedes that goal. As long as we are in a broken world, happiness will be elusive to a degree, and at best will be felicitas, which means real but impermanent happiness.
Ancient Greeks, unlike their modern descendants who are largely occupied these days with fixing their economy, spent time studying human dispositions. They were good psychologists. Their gods and goddesses were essentially symbols of human characteristics. There were many deities who represented varying attempts at happiness, although some of their philosophers, like the Cynics and Stoics, did not think there was much of a chance at felicity. There were, for instance: Bacchus — drinking; Hypnos — drugs; Hermes — sports; Dionysius — partying; Aphrodite — sex; Tyche — good luck; Hygieia — health; Thalia — comedy; Momus — silliness and gossip; and Nemesis — revenge on enemies.
Saint Paul was familiar with that ghostly pantheon and politely confronted their clients in Athens. He did not mock or insult them. But he did declare to them that he knew the one true God who is the source of all true joy and for which those idols were lame substitutes:
Being then the children of God, we ought not to think that the Divine Nature is like gold or silver or stone, an image formed by the art and thought of man. Therefore having overlooked the times of ignorance, God is now declaring to men that all people everywhere should repent, because He has fixed a day on which He will judge the world in righteousness through a Man whom He has appointed, having furnished proof to all men by raising Him from the dead. (Acts 17:29–31)
Most of the philosophers were unmoved because they liked hearing themselves and none other. But one of them, Dionysius, and a woman named Damaris, and "a number of others" accepted Christ. Their stories are unrecorded, but as Christ never lied, we know that they inherited a happiness higher than felicitas, and that is beatitudo — the endless joy of God's presence.