(These are initial sketches provided by Mark Collins, which will need revision.)
Ask anyone who calls themselves a Humanist what a Humanist is and likely you'll get a different answer, and it is often confused with Secularism. Indeed, there is a the modern redefinition of Humanism which embraces non-theism, which I will differentiate here as secular Humanism.
The Wikipedia definition is perhaps a good place to start: it describes Humanism as a philosophical approach that emphasizes the agency of human beings, collectively and individually.
Whichever interpretation of the approach we take, there is a common thread which is not to pay heed to suggestions of supernatural or transcendent involvement with human affairs, but instead to focus on what we can achieve together as people. Some use the term to deny either the existence or the relevance of God (so not strictly atheism or agnosticism or even agnostic atheism!).
Types of Humanism
The ideas of Humanism (focusing on - and trusting in - reason and knowledge rather than the supernatural) have their roots in the ancient societies of China, India, Greece, Medieval Islam and the Icelandic Sagas.
Revival in the study of classical antiquity (starting in Italy, spreading to Western Europe, c14 - c16) was associated with learning and the humanities. Most adherents were religious, seeing humanism as a way of purifying Christianity or returning to the simplicity of New Testament teachings, rejecting what they saw as the complexities of medieval theology. The focus was on society - educating and encouraging engagement with civic life - and seeking to revive the cultural legacy of classical antiquity. This led to the printing press and eventually to the Protestant Reformation.
Whilst most modern humanists would probably not embrace any religious ideology, the historical roots for the embracing of learning and social enablement are clearly to be seen.
The first Humanist Manifesto (1933, Chicago) collected together reason, ethics, social and economic justice as a more satisfactory basis for organising human affairs than dogma and using the supernatural as the basis for morality. However this first manifesto (Humanist Manifesto I) reads in a rather dogmatic manner, even presenting itself as a 'New Religion'. It was indeed signed by 15 Unitarian ministers and theologians, and contained the following statement.
"There is great danger of a final, and we believe fatal, identification of the word religion with doctrines and methods which have lost their significance and which are powerless to solve the problem of human living in the Twentieth Century. Religions have always been means for realizing the highest values of life. Their end has been accomplished through the interpretation of the total environing situation (theology or world view), the sense of values resulting therefrom (goal or ideal), and the technique (cult), established for realizing the satisfactory life. A change in any of these factors results in alteration of the outward forms of religion. This fact explains the changefulness of religions through the centuries. But through all changes religion itself remains constant in its quest for abiding values, an inseparable feature of human life."
Reading this it is interesting how many terms now have a rather different inflection, even meaning, but the examination of the evolution of religion is a very interesting matter to consider, and what the implications of the evolution of 'revealed truth' has about the very nature of revelation.
This approach to humanism can be described as Religious Humanism - no longer seeking to purify old religions, but to replace them entirely with a new one.
Paine called himself a theophilanthropist, a word combining the Greek for "God", "love", and "humanity", and indicating that while he believed in the existence of a creating intelligence in the universe, he entirely rejected the claims made by and for all existing religious doctrines, especially their miraculous, transcendental and salvationist pretensions.
The Wikipedia definition is perhaps a good place to start where it describes Humanism as a philosophical approach that emphasizes the agency of human beings, collectively and individually.
Whichever interpretation of the approach we take, there is a common thread which is not to pay heed to suggestions of supernatural or transcendent involvement with human affairs, but instead to focus on what we can achieve together as people. Some have put it to deny either the existence or the relevance of God (so not strictly atheism or agnosticism or even agnostic atheism!).
Secular, properly defined, means the separation of religion and the affairs of state (politics if you will). [See Secularism] However this can only be at a societal level, as any fair political system (opportunity for discussion of 'fair') cannot exclude people based on their religious belief, so religious people with religious motivation will be involved in the political dialogue.
Jim Palmer seems like someone worth linking to, but we don't seem to have an obvious place in Humanism to put that link yet.
Adding to the conversation: I recently came across this video: How do we know what's true?', posted on humanists.uk, and narrated by Stephen Fry. It's a clear, attractive presentation of some common ideas about truth and how to find it. There are a good number of accurate and helpful details in it, but the overall message is quite untrue and misleading: it claims to tell us about the history how how people have sought truth, but the history it tells is almost entirely fictitious, and the truth it claims to talk about is missing all the important areas we need in order to live as humans. The overall impression is one of attending a Humanist Sunday School: a cut-down version of reality, designed for children who can't cope with the complexities of the real world. Sadly, many children take their Sunday School version of Christianity with them into the adult world, and decide it is inadequate - and I fear that presentations like this will damage Humanism in a similar way.
A couple of paragraphs from the Introduction are repeated near the end under 'Modern Humanism' - presumably they should be deleted from the Introduction?
The Introduction also says, "Some use the term to deny either the existence or the relevance of God (so not strictly atheism or agnosticism or even agnostic atheism!). " I fail to see how this doesn't fall within the scope of agnosticism? Surely (when used this way) Humanism is a branch of agnosticism?
It seems to me that, if you ask whether it is fair to describe Humanism as a form of religion, the main issue is how you define 'religion' - which is a traditionally difficult term to define, because any attempt to define it upsets a large number of people. (So I plan to attempt to do it fairly soon ...)
The big conceptual challenge to Humanism is the claim that it rests upon concepts which have traditionally been derived from religion and faith, such as morality and justice. And it is hard to distinguish Humanism from religion when (for example) "trusting in reason and knowledge rather than the supernatural" is the claim made by the earliest Buddhists when they contrasted their pragmatic approach to life with the beliefs and practices of the Hindu community. It rather depends on how you define reason and knowledge, and how you can access specific examples of reason and knowledge without relying upon some kind of underlying belief. (Many scientists today say this cannot be done - certainly, it is not trivial.)
It seems to me that there are two strands to Humanism. There is the aspect of treating other people well, of being caring and respectful and non-discriminatory. And there is the epistemological aspect of how we arrive at truth: Humanists would say that we must arrive at truth by Reason and Science, rather than by faith or acceptance of a tradition. They are linked, in that treating others with respect is a reasonable and rational thing to do, whereas discriminating because your religion, or your prejudice, says you must is irrational.
We really need a Venn diagram here, because a person can be in any of these categories or none. Being an atheist does not make you a humanist: Stalin and Mao Tse-Tung and Pol Pot were atheists but definitely not humanists. (I haven't used Hitler as an example as he wasn't an atheist). Robespierre was a product of Enlightenment Rationalism, but extrapolating those ideas to exterminating everyone who was not a Rationalist is not a Humanist principle. Most Christians that I know are very nice, caring people, but so are most other people. I suspect the proportion of nice/not nice people is about the same. However Christians in an English Anglican church (such as the one that I still associate with) are likely to have compromised their views on morality so as not to offend anyone, and will have views not that different from those who identify as humanist. whereas Christians in a Southern Baptist church in Tennessee will hold decidedly non-humanist views on abortion and homosexuality, but may still be a nice person, though I imagine they would have to live with a lot of cognitive dissonance to stay nice.
If a Christian arrives at their beliefs through a process of reason, e.g. by concluding that evolution by natural selection alone is unlikely, then perhaps they are more Humanist than an atheist who has always been one because their parents were and has never thought it through. (My own conclusion, such as it is, is that the science is sufficiently inconclusive that agnosticism is the most honest position). Many people reject organised religion and then believe all sorts of irrational stuff: ghosts; "you become an angel in heaven when you die"; horoscopes etc; again not humanist, and they may or may not be treat other people with respect and so qualify as humanist in that aspect.
So the essential part of being a humanist is to treat people well, whereas it is probably possible for humanists to have a range of views on religion. However, to have a religion that makes you discriminate others or persecute them would not be compatible with humanism. To have arrived at your religous views (including atheism) without thinking them through is not humanist, and neither is holding rigid untestable beliefs that put you in conflict with others, or gives them false hope e.g. that prayer will heal or protect them.
I like the two aspects you identify, and think that distinguishing these aspects is helpful. But I don't think they give you what you need here.
I fully agree with treating people well, and that reason and science are important ways to find truth. But ...
I think there are problems if you try to define any of these terms - religion, science, humanism - too closely. Scientists, Theologians, and Philosophers of all opinions try to make exact definitions, but these rarely fit the real world.
I do not say that there are no absolutes, but it can be difficult to find them. "Science is itself a tradition...": true in that it has a way of functioning that develops over time. There are certainly some scientists that become very dogmatic about their theories (often including Evolution), but the point of science is to accept that we do not yet know the answers and try to use experiment and testing of results and peer review to find those answers. Traditional, dogmatic Religion claims to have the Truth, but the source of this will be a Holy Book which is stated as an act of Faith to be true. The theology that follows from that often follows an internal logic in the same way as science does, but this can fall apart if the underlying assumptions are challenged. And the 21st century manifestations of moderate Christianity and moderate Islam have adapted to fit in with modern culture, and in so doing are open to charges of reflecting society rather than their own traditions - conforming to "The World", as the Plymouth Brethren would say. The Christianity that I experience now is not the same as that in which I grew up in the 1960s and 70s. Humanism likewise, has a set of general principles rather than a rigid definition - it doesn't pretend to have a rigid set of beliefs within the general principles, so there is plenty of room for debate about the details, at least among the Humanist UK organisation. (Though again, this reflects the 21st Century: up until at least the mid-20th Century it was not just Christian denominations that had bitter in-fighting about small issues of policy or theology; so did the Political Left - Marxism, Trotskysim and dozens of other left-wing sects, and the Right also).
"Human life is not only about truth: it is also about values, dreams, aspirations and other things which reason and science cannot tell us about". Absolutely, but Humanism would not disagree with this.
"Reason and science can tell us some of the consequences of being caring and respectful, but they cannot say that we should act in that way: you cannot derive an 'ought' from an 'is', as the saying goes". Again, this depends on a rigid definition of Ought and Is. Some proponents of Reason have been highly dogmatic - Stalin, Robespierre. Sometimes it is appropriate to be dogmatic: Wayne Couzens had a dream and aspiration to rape and kill a woman, and he achieved that aspiration, but at the expense of Sarah Everard's dreams and aspirations: so from that we impose an "ought" (or "ought not"). As a Nurse I remember the Manager of a Forensic Secure Unit saying that killers are no different from the rest of us; they just throw away the rule book. There has to be a rule book, at least for the broader aspects of human behaviour such as murder; but once upon a time the rule book might have said that we must all attend church on Sunday; now it doesn't. So generally, we can make a pretty good stab at defining, or at least suggesting, what we should and should not do.
"Are you certain about the truth of your last paragraph? If so, is that not a 'rigid and untestable belief' which will inevitably put you in conflict with others who see life (or understand Humanism) differently?" I think it would only put me in conflcit with people who's views were more rigid than mine. That may include some humanists, though if they were too dogmatic, I would question whether they could be humanists. Just as Christianity has a menu of truths that all its adherents would agree on with room for discussion within that menu, so does Humanism. The fact that my beliefs changed over a fifteen year period, and continue to do so, suggests that I test my beliefs.
I need to say that I am using the term Humanist as a very general umbrella term of my position, but I am not going to subscribe to any one set of beliefs. Humanists UK seem a pretty reasonable bunch of people, who leave room for a range of interpretations, but in the end I follow my own path - I won't say that I follow my own convictions as I don't have many of those. I am open to the possibility of the existence of something that could be defined as God. I'm not even a good Humanist, any more than I was a good Christian. Today, my wife suggested that I might consider cooking the supper for once, and my daughter said "Dad, as a Humanist you should do what would make mum happy, and that would make your life easier". Great, thanks a lot, Alice! Protestant Christianity is right insofar as it acknowledges that we all need Grace, as we can never measure up even to our own standards, let alone those of a particular creed.