Introduction
In their criticisms of the creationism and intelligent design movements, particularly in legal cases, scientists and others are quick to point out (correctly!) that these movements are inherently religious. For example, in the 2005 legal case “Kitzmiller vs. Dover Area School District,” where parents challenged the Dover Area School District’s decision to require intelligent design material presented in high school classrooms, the plaintiff attorneys forcefully argued that the school district’s professed “secular purposes” in promoting intelligent design material were a sham, and that the “designer” in intelligent design theory is clearly the God of Judeo-Christian theism [Jones2005, pg. 25].
A frequent rejoinder by creationists and intelligent design writers is that science (and modern secular thought in general) is also founded on a religion, namely “secular humanism,” and it is not fair to bar creationism and intelligent design yet still allow evolution, for instance, to be taught with full approval. For example, Kenneth Ham, the leader of Answers in Genesis, a leading creationist organization, writes [Ham2015]:
In almost all of today’s government-run educational systems, the religion of secular humanism — with its foundation of naturalistic evolution based on man’s word/beliefs about the past (molecules-to-man evolution) — is guised in textbooks, lectures, and secular museums as so-called “science.”
Similarly, David Noebel, founder of Summit Ministries, argues that secular humanism “is a full-fledged religious worldview.” He deplores the fact that secular humanism has been granted exclusive access to public schools, claiming to be scientifically derived and morally neutral, when it is not [Noebel2007].
So what are the facts here? Is secular humanism a religion? Is science dependent on secular humanism? Is secular humanism an entirely secular philosophy?
What is secular humanism?
While the humanist movement in general, and secular humanism in particular, is a broad-based philosophy encompassing numerous schools of thought, the definition of the movement is best taken from “manifestos” issued by the American Humanist Association. Their most recent version, issued in 2003, declares that “Humanism is a progressive philosophy of life that, without supernaturalism, affirms our ability and responsibility to lead ethical lives of personal fulfillment that aspire to the greater good of humanity.” [Humanist2003]. Additional details are given in the 1973 manifesto [Humanist1973]:
Any account of nature should pass the tests of scientific evidence; in our judgment, the dogmas and myths of traditional religions do not do so. … As nontheists, we begin with humans not God, nature not deity. … We affirm that moral values derive their source from human experience. … Reason and intelligence are the most effective instruments that humankind possesses. … To enhance freedom and dignity the individual must experience a full range of civil liberties in all societies. This includes freedom of speech and the press, political democracy, the legal right of opposition to governmental policies, fair judicial process, religious liberty, freedom of association, and artistic, scientific, and cultural freedom. … The principle of moral equality must be furthered through elimination of all discrimination based upon race, religion, sex, age, or national origin. This means equality of opportunity and recognition of talent and merit. …
Does science require secular humanism?
As mentioned above, creationist and intelligent design writers, in response to claims by scientists and others that teaching creationism and/or intelligent design in public schools is a violation of the separation between church and state, often respond by saying that science is also based on a religious movement, namely secular humanism (they sometimes replace “secular humanism” with “scientific materialism”). But science is not based on secular humanism — instead, secular humanism claims to be based on science.
In any event, with or without connection to secular humanism or other philosophical systems, scientists have little choice but to seek explanations of nature based on natural laws. As the National Academy of Science explains [NAS2008, pg. 10]:
In science, explanations must be based on naturally occurring phenomena. … If explanations are based on purported forces that are outside of nature, scientists have no way of either confirming or disproving those explanations. Any scientific explanation has to be testable — there must be possible observational consequences that could support the idea but also ones that could refute it. [italics in original]
Similarly, scientific philosopher Robert Pennock explains that a reliance on empirical evidence and natural law is essential to the scientific method [Pennock2001, pg. 89-90]:
Once such supernatural explanations are permitted they could be used in chemistry and physics as easily as Creationists have used them in biology and geology. Indeed, all empirical investigation beyond the purely descriptive could cease. … Methodological Naturalism is not a dogmatic ideology that simply is tacked on to the principles of the scientific method; it is essential for the basic standards of empirical evidence.
In other words, claims that modern science is inextricably based on secular humanism really don’t make sense. Science has its own crisply defined definition and methodology, which does not involve these other movements.
Secular humanism and religion
So let us return to the original question. Is secular humanism itself entirely religion-free, or not?
First of all, it is worth observing that scientists also take faith with them into the research laboratory. As British philosopher Alfred North Whitehead has noted [Whitehead1967, pg. 17-19, 27]:
Faith in reason is the trust that the ultimate natures of things lie together in a harmony which excludes mere arbitrariness. It is the faith that at the base of things we shall not find mere arbitrary mystery. The faith in the order of nature which made possible the growth of science is a particular example of a deeper faith.
British philosopher-theologian Keith Ward observes that religion and materialist philosophies such as humanism have more in common that either might like to admit [Ward2008a, pg. 51-52]:
At a usually tacit level of awareness, both the atheist and the theist participate in a common faith. They both believe that reality is intelligible and that truth is worth seeking. What theology adds is that the existence of God — that is, of Infinite Being, Meaning, Truth, Goodness, and Beauty — provides an adequate justification of this belief, as well as an answer to the question of why the universe is intelligible at all.
Furthermore, it is not clear that secular humanism (or any other humanism-related school of thought) can completely disengage itself from theistic religion. As Yuval Noah Harari argues in his 2015 book Sapiens, even though humanist philosophies sanctify human and explicitly disavow belief in Judeo-Christian theism, nonetheless they are founded on monotheist beliefs. After all, the humanist belief in the free and sacrosanct nature of each individual person is a direct restatement of the traditional Judeo-Christian belief in free agency and eternal souls. Thus, “without recourse to eternal souls and a Creator God, it becomes embarrassingly difficult for [humanists] to explain what is so special about individual Sapiens.” [Harari2015, pg. 232].
For that matter, it is highly questionable that humanism is really rooted in science, particularly in its assertions of the rights of individuals. As Harari explains, “There are no such things as rights in biology”, and “There is no such thing as [liberty] in biology” [Harari2015, pg. 112].
Summary
In summary, it is not true that science is founded on secular humanism, or that to teach science (e.g., evolution) in public schools is tantamount to teaching secular humanism. Science has its own definition and its own methodology, quite independent of these other movements. In particular, the presumption of natural law and the disallowance of supernatural effects are essential to the enterprise of empirical science.
But it is also true that “secular humanism” is not entirely “secular.” Humanist philosophies are inextricably connected to the Judeo-Christian notion of the worth of individual souls. And any attempt to define secular humanism exclusively in terms of scientific entities, such as biological or physical systems, is doomed to failure.