The author of our Declaration, Thomas Jefferson, carefully distinguished in private letters between the modern life devoted to the pursuit of happiness and happiness itself. He says that Epicurean philosophers found happiness through their serene recognition of the truth of atheistic materialism, and so in their capacity to live truthfully beyond hope and fear—the twin sources of the miserable restlessness of the Lockean individual.
That happy philosopher, for Jefferson, is a very rare and most fortunate human occurrence. Even in times of Enlightenment his way of life would not be possible for most people.
Ordinary people, Jefferson observes, are guided by nature to happiness through a “moral sense,” an instinct that caused them to find pleasure in virtuously benefiting their fellow human beings in society. If there were no natural connection between happiness and the performance of social duty, then we would be absurdly unfit by nature for the social lives we must live. The benevolent principles that correspond to our natural moral sense, Jefferson claimed, were most perfectly expressed by Jesus. Following his natural teaching is the way to human happiness.
To see Jesus as more than the model natural being—as God—is to muck up true morality with ridiculous mystifications--not to mention false hopes and fears. That’s why Jefferson engaged in the project of editing/shortening the New Testament with his knowledge of natural morality in mind. It's his Jesus he's recommending to us.
The ordinary moral person achieves happiness by following the biological or basically bodily instinct we’ve been given. Instincts--like muscles--are strengthened through exercise, through habituation. Being good is acting on one's social instinct to do good.
Such moral sense is distorted and even diminished, Jefferson claims, by reading moral philosophy--which, for Jefferson, is pretty much hypocritical moralism. On this front, Jefferson hated Plato and the Platonists the most, and the Stoics only somewhat less. Epicurus he ranks higher than all the other philosophers for being upfront on the fact of the incompatibility between philosophy and morality.
The view that the natural moral sense is the source of human happiness came to Jefferson through the Scottish Enlightenment. Thinkers such as Adam Smith aimed to soften or socialize Locke’s individualism through the cultivation of moral sentiments. That sentimental Enlightenment went on to decisively influence the optimism of Darwin.
Darwin concluded that our species is not, in the most important senses, different from the others. The successful intention of nature is that all the animals have enjoyable or happy lives. And it’s our basically unconscious determination by nature that should give us confidence that our existence is good. Darwin held that reason is a tool that serves our social instincts, and so that human beings would progress morally as they progressed intellectually.
The Epicurean Jefferson wouldn't have made that connection between moral and intellectual progress. He didn't think that the mind exists to serve the body of the social animal. He thought, instead, that there was deep tension between what's best for the liberated philosopher or scientist--the being who's, so to speak, pure mind--and what's best for the social animal. It wouldn't have surprised Jefferson to have seen social instincts atropying in the direction of apathetic indifference in our enlightened or pop scientific time.
We do have to admit there’s a lot of truth to what Darwin says about the natural foundation of human happiness. The Lockean or individualistic or libertarian view is that happiness is subjective; what it is varies from free individual to free individual.
But there’s a lot less variation, the sociobiologist E.O. Wilson says, than it first appears. For most human beings—most social animals—happiness is something like the opposite of loneliness. For the most part, studies show that married people are happier than single people, people from large families are happier than people from small families, and people with lots of close friends are happier than people with just a few.
Happiness also correlates strongly with faithful involvement in religious communities, active participation in political life, and worthwhile work with others. Happiness usually depends on really developing the attachments—a non-Darwinian would say the personal love—that come from doing what social animals do. No study confirms the individualistic thoughts that love is for suckers or hell is other people.
Wilson adds, quite realistically, that there are a few people who want to be left alone. And what's usually true, Jefferson remind us, isn't true for Epicureans such as himself. Jefferson, I think, wouldn't have thought that Darwin explains it all. I would add, you won't be surprised to know, that Darwin and Darwinians can't even explain what's most happly personal about love.