Stephen Law has a very good list of general humanist traits. I can go with this:
1. Secular humanists place particular emphasis on the role of science and reason.
2. Humanists are atheists. They do not sign up to belief in a god or gods.
3. Humanists suppose that this is very probably the only life we have.
4. Humanists usually believe in the existence and importance of moral value.
5. Humanists emphasize our individual moral autonomy and responsibility.
6. Humanists are secularists in the sense that they favour an open, democratic society and believe the State should take neutral stance on religion.
7. Humanists believe that we can enjoy significant, meaningful lives even if there is no is a God, and whether or not we happen to be religious.
But then he raises an objection I wouldn’t have even considered:
Now some readers may be thinking, ‘But hang on, you haven’t mentioned naturalism. Surely secular humanists also sign up to naturalism, right? They reject belief in the supernatural. So why no mention of naturalism here?
Really, I wasn’t at all worried about it — to the point I was baffled why we even needed to discuss the fine points of naturalism. Then he explained that it was a significant issue among philosophers.
…note that naturalism is pretty controversial even amongst atheists. Take the professional philosophical community. The 2009 Philpapers survey of the opinions of professional philosophers and graduate students revealed that less than 15% of professional philosophers and graduate students are theists. Yet only a little less than half of them sign up to naturalism. That leaves around 35% who are neither theists nor naturalists. Why bar them all entry to the secular humanist club, particularly when many of them will be fully in agreement with points 1-7 above (which are, it seems to me, the points that really matter)?
I confess, my first thought was “silly philosophers, fussing over the precise meaning of words…”, and thinking that the scientific community rarely seems to do surveys of what scientists believe about metaphysics. But then…I realized that most scientists have a nice little dogma about that very issue. We don’t wrestle with the concept because we already know what to think, which is not a good state of affairs. Maybe we should listen to philosophers more.
Here’s our dogma, which has been recited at my more times than I care to remember, usually by people making excuses for religion: “A scientist has to be a methodological naturalist, but not a philosophical naturalist.” The former is a practical approach to what you do in the lab, the latter is about what you believe about the nature of the universe. You hear it a lot from the NCSE, as a rhetorical tool to reconcile religion and science.
It’s always bugged me. Here we are, making hair-splitting decisions about delicate distinctions in the philosophy of science, and we reduce them to a nice pat dichotomy, two buzzwords that we can use to place people’s beliefs into two specific categories, usually to say that we can ignore one perspective. Yet when I’ve actually thought about the two categories, I have to say that my position is messier. Short answer: I guess I’m a philosophical naturalist, because I don’t believe there is any non-natural processes working in the world. But what would be an unnatural process? If a supernatural cause has an effect on the natural world, doesn’t that mean it is now amenable to scientific study? I don’t exclude the operation of different laws outside my universe, only that they’re going to have to accept a kind of natural straitjacket to impinge on us here. Maybe I’m a kind of utilitarian naturalist? I don’t know. Maybe I should study more philosophy.
Law makes the point that naturalism is a murky mess, and I have to agree with him.
Philosophical doubts about naturalism tend to spring, first, from concerns about whether naturalism is a well-defined concept. What is naturalism (or metaphysical naturalism, to be precise)? A sceptic’s usual first port of call is to say that naturalism consists in the rejection of belief in the supernatural. But what is the supernatural? Why, it’s that which isn’t natural, of course! But now notice that these explanations of naturalism and supernaturalism are, as they stand, entirely circular and uninformative. So far, no significant meaning has been attached to either term. It’s harder to define ‘naturalism’ than you might think (though note I don’t say it can’t be done).
I’ve used that “methodological naturalism” excuse in the past, and I do bring it up in my classes, but I’m increasingly reluctant to trot it out in any kind of argument. It seems to me to be a dangerous rhetorical trap for scientists: by accepting it, you’ve moved the battleground from an area where you have expertise, the physical and logical evidence for evolution, to the area of the philosophy of science, and most of us (me included) are totally unqualified to discuss it. A smart creationist or theist could spin you up, down, and all around, leave you confused and staggering, and get a technical K.O. against you.
If you want to argue this stuff, it’s essential to know where your strengths lie…but also your weaknesses.