The thinkers of the Enlightenment were never under any illusion that people are perfectly rational and modern cognitive psychology affirms that we’re all subject to fallacies and biases and systematic errors. On the other hand we must be capable of reason or we’d never be able to establish that humans are irrational because we’d have no benchmark of rationality against which to compare human cognition and we’d have no way of trusting the comparison unless we were doing it rationally. So clearly we have the capacity to be rational and the question is how can we set up institutions and norms that concentrate and catalyse that capacity to make us collectively as rational as possible, even if no individual among us is
perfectly rational and these norms would include: Free speech, you don’t get to impose your beliefs on others but you have to allow them to be criticised and flaws to be pointed out; logical analysis, knowledge of non sequiturs and fallacies in reasoning; empirical testing for beliefs that are about the empirical world and in general the norms of truth-telling, fact-checking and open criticism and debate.
Even though science has been associated with destructive technologies particularly nuclear weapons and pollution, science as a whole has brought enormous gifts to the world. It has more than doubled our lifespans by replacing muscle with machinery, it has emancipated slaves and women and children. It’s allowed us to see the world, to experience the world’s cultures and cuisines. The challenge that faces is how to deploy technology in a way that delivers the maximum human benefit with the least harm to the environment.
Well reason and science by themselves won’t lead to moral ends because they’re just ways of getting from A to B and they don’t say what the B should be. Humanism is the critical ingredient to an enlightenment, informed worldview because it explicitly stipulates what science and reason by themselves cannot mainly, what’s valuable, what matters and what it stipulates is that human wellbeing - and the wellbeing of other sentient creatures - but life, health, happiness, love, stimulation, richness of experience, those are the things that we ought to maximise and deploy reason and science in service of.
Humanism is possible because we’re endowed with a sense of sympathy, we have an ability to be concerned with the welfare of others. Even if by default our sense of sympathy is rather narrow and we apply it merely to our blood relatives, our circle of friends and allies, to cute little baby animals. We can expand this circle of sympathy by mixing people and ideas, by journalism, by narrative fiction, by mobility, by interaction and debate.
Even by reason, by the fact that if I can’t convince you that you have to respect my interests and not vice versa just because I’m me and you’re not and hope for you to take me seriously, as soon as we have to come to an agreement we’re bound to expand our circle of sympathy to encompass one another. As we do that we don’t always succeed but we don’t always fail either and if we retain the practices that make us measurably better off, then progress can accumulate.
I think there’s an imperative to champion the values of humanism because they are very much under threat from forces of traditional religion, of nationalism, of populism, of the dilute forms of fascism that sometimes shade into populism and nationalism, and a problem with humanistic values is that they tend to fade into the background, they become so successful in setting the course of democratic governments, organisations, of institutions, of international cooperation, of schools and hospitals and universities and charities and NGOs, that people can forget that it really is a distinct value commitment and if we forget that then enlightenment values can just become a blend status quo, or the establishment, and then take the blame for everything that goes wrong in society, for which there will always be many examples.
So defenders of alternative systems, like religions and nationalist movements, they know what they stand for, they can recite slogans and gather under icons. Humanists have to be able to articulate the principles that they believe in as well.