Answer
According to Duke University Philosophy Professor Alex Rosenberg, scientism is the worldview that all atheists share. It “is the conviction that the methods of science are the only reliable ways to secure knowledge of anything, that . . . science provides all the significant truths about reality. . . . Being scientific just means treating science as our exclusive guide to reality” (The Atheist’s Guide to Reality: Enjoying Life Without Illusions , W. W. Norton & Company, 2011, p. 6–8). In other words, our religious or philosophical beliefs do not appropriately inform our understanding of a given claim. Only science defines our reality.
Followers of scientism hold to the idea that science alone is trustworthy and that science alone can provide answers to moral questions. The result of this belief system is that its supporters, in their support for abortion, for example, attempt to find a scientific basis to say that human embryos are not human; and they present controlled breeding programs such as eugenics as scientifically valid, despite the moral repulsiveness of such programs.
University of Miami Philosophy Professor Susan Haack goes a step further, saying that scientism is “an exaggerated kind of deference toward science, an excessive readiness to accept as authoritative any claim made by the sciences, and to dismiss every kind of criticism of science or its practitioners as anti-scientific prejudice” (Defending Science—Within Reason: Between Scientism and Cynicism, Prometheus Books, 2007, p. 17–18). Such scientific extremism could be described as a sort of religious radicalism. Indeed, scientism is often used to explain away the existence of God.
Interestingly, science often uses things that are not “scientific,” such as introspection or memory, in order to provide knowledge; thus, we can rightly ask, how can non-science observations lead the proponent of scientism to accept the resulting hypothesis as valid? What is the basis for the truth proposition without the ability to make purely scientific measurements unaffected by bias? Scientism raises more philosophical questions than it answers.
One philosophical issue raised is the fact that the thesis of the correctness of natural science is not itself a product of natural science, so it does not meet its own criteria. If we cannot know, scientifically, that scientism is true, why should we believe scientism in the first place?
We as human beings have moral and religious beliefs. Just as scientism sees fit to define itself with knowledge from outside the scientific realm, those who are not adherents of scientism inform their beliefs with knowledge from outside the scientific realm, viz., from religion and philosophy. And there is much in life that cannot be measured, quantified, or defined scientifically—everyday issues concerning trust, love, and relationships, for example, are beyond the realm of science. As C. S. Lewis wrote, “To be incommunicable by Scientific language is, so far as I can judge, the normal state of experience” (Christian Reflections, “On Religious Language,” 1967, p. 138).
The weakness of scientism can be seen in the debate between evolution and creationism. Neither evolution nor creationism can be proved via controlled laboratory experiments using well-defined principles of the scientific method; therefore, how can one reject either one out of hand simply through the application of fundamental beliefs? Scientism relies upon untestable assumptions yet still draws conclusions that its adherents feel are favorable, and Christians draw conclusions using observations of life, behavior, and even thought patterns influenced by the Holy Spirit.
At the end of the day, scientism, with its over-valuation of science, is a religion, just as Christianity is a religion. One offers hope for the future and eternal life. The other does not. When the Book of Life spoken of in Revelation 20:12 is opened, you will want your name to be found there, with the names of all the others who have trusted Jesus Christ. It is Jesus who saves, not our understanding of science.