Are there any good reasons to think we are purely physical, and not a unity of soul and body? Last week I considered four reasons that fail. This week I’ll consider a fifth, along with four reasons this is wrong thinking.

Reason #5: Blind Faith in Science

When all else fails (when no arguments against substance dualism succeed and no arguments for Physicalism are plausible), some refuse to accept the logic and data in favor of Substance Dualism. They believe that although we don’t yet have a physical (scientific) explanation, if we keep searching long enough and hard enough, eventually we will be able to explain human persons in purely physical terms.

This is a specific epistemology (a theory of knowledge—a view of how we know what we know) that we inherited from the Enlightenment. It is known as “Scientism.” 

Let me be clear that I believe science is a very good thing, allowing us to study and learn much about the physical world. Those called to scientific fields have a high and noble calling, providing a great service through their scientific research, writing and teaching.

 However the Enlightenment absolutized science, saying it is the only way to know something. So if we can find a scientific explanation, then we have knowledge. We have facts. We have a valid explanation. But if we can’t find a scientific explanation, then we merely have opinions and beliefs. So, according to Scientism, philosophical reasoning is of no help in giving us knowledge of anything, including what it is to be a human person.

The result of this approach to knowledge is that we must reject all philosophical arguments in favor of Substance Dualism and against Physicalism, simply because they are not “scientific.” Instead we must pin all our hopes on science one day providing an adequate answer to the question “What are we?”

I call this the “blind faith in science” approach. There are at least four problems with this approach to knowledge.

1. It “Begs the Question”

This approach assumes that only physical things exist, and so concludes that only science, which explains physical reality, is the only way to discover facts or truth.

Of course, if one begins with this assumption, then Scientism is the conclusion—if all that exists is physical, then science is the only way to know truth. But why begin with this assumption? There is simply no good reason to do so. The “Enlightenment” bequeathed this assumption to us. But this is a sociological reason many begin with this assumption. It is not a rational reason. And so it is not a good reason.

If one doesn’t begin with this assumption, but allows for the possibility of immaterial things existing, then they are not the kind of things that can be known by science, which by definition explains only physical reality. In this case truth of immaterial realities will be known through other disciplines, such as philosophy and theology.

An important implication is that science, and thus scientists, must remain silent concerning the existence and nature of immaterial reality. Being outside the physical realm, it is outside their areas of expertise. Unfortunately, scientists often fail to understand this (think of Carl Sagan’s famous claim that “The Universe is all there is, and was, and ever will be” and many of Richard Dawkins’ writings.) As non-scientists should not make scientific claims without proper training (i.e. scientific training), scientists should not make claims about immaterial reality without proper training (i.e. theological or philosophical training).  

2. Science Itself Depends on Philosophical Assumptions

If only what is known by science is “fact” “knowledge” or “truth,” then scientists must reject much of what they assume is true in order to practice science.

For instance, science assumes a uniformity of cause and effect. This is the basis for repeating an experiment enough times so that one can conclude that X causes Y. This is a fair assumption. Yet it is not a scientific assumption. It is a philosophical assumption (an assumption in one’s philosophy of science) that is made before the scientist enters the lab to run the experiment.

Furthermore, it is a philosophical assumption that is grounded in a theological assumption–that God is a God of order who created a universe that can be known through the observation of cause-and-effect relationships. This is why science flourished among Christian thinkers such as Robert Boyle, Isaac Newton, Johannes Kepler, Carl Linnaeus, Michael Faraday, James Clark Maxwell, Gregor Mendel, and Lord Kelvin. Science did not flourish in the East, where there were different (pantheistic) assumptions.  

Another philosophical assumption brought to the practice of science is the assumption that the future always reflects the past. It is this assumption that allows one to predict something based on the data of past experiments. This is a very fine assumption. It is just not a scientific assumption. 

The Laws of Logic are also assumed to be true in the practice of science. Again, these cannot be proven by science, but are brought into the work of the scientist as assumptions undergirding her work as she seeks to develop rational explanations of observed phenomena.

The same is true of ethical values, such as the value that scientists should always report data accurately. This is necessary for science to be done. But it is not discovered in a beaker. It is not known from science, but must be known before science in order to do science.

Therefore, there is much that can and is known that is not known by science. This is a second reason that Scientism can’t be right.

3. If Scientism is True, It Must be False!

 Scientism is logically self-defeating (see here for a discussion of what it means for a view to be self-defeating). Scientism claims that Science is the only way to know something. However, this claim itself is a claim of something known.

So, if Scientism is true this claim must be known scientifically. But it cannot be observed in a beaker or through any other scientific apparatus. No, it is a philosophical belief. It is a philosophy of what can be known—an epistemology. So if this philosophical assumption is granted, Scientism may be true. But to grant this philosophical assumption is to already agree that Scientism is false—that there are truths beyond scientific truths (at least this one).

4. The History of Science Counts Against Scientism

The history of science does not tell this story those who promote Scientism thinks it does. The history of science is the story of many scientific theories, and even “truths” that everyone “knew” to be true at one time, being overturned and now rejected as errors. As has often been said, “He who marries science today will be a widow tomorrow.”

The story is not just one of theory refinement, as a previous theory is modified to fit new data. Rather there are many of what Thomas Kuhn called “paradigm shifts” in which an entire paradigm is thrown out in favor of an entirely new paradigm. This is true even if some or most of the same words are retained, such as the shift from Newton’s to Einstein’s theory of space, time, motion and mass.

As a result, some philosophers of science argue that we have completely misunderstood the end and aims of science. They argue “Scientific Realism”—the assumption that the goal of science is to give us a true (or approximately true) understanding of the world—is too lofty a goal, and too much to expect from science.

Instead they claim the more rational approach is “Scientific Anti-Realism”: science should be expected to give us “useful fictions” rather than truth. In other words, the end of science is to help us develop technology that gives us mastery over nature to improve our lives. However, this does not require these scientific beliefs be true. They argue this is a lesser, more realistic and more historically accurate understanding of the aims and ends of science.

Good people come down on either side of the Scientific Realism/Anti-Realism debate (I tend to be a Realist in the more established areas of science and an Anti-Realist in the newer areas still developing, such as quantum physics). But the mere fact of the debate, and two tenable positions, is reason enough to reject Scientism.

This is even more the case when other disciplines that provide knowledge, such as philosophy, have been around for thousands of years without changing much. (Most of the logic and philosophical arguments we use today date back to Plato and Aristotle in the 4th Century B.C.)

Conclusion

For these four reasons I believe Scientism, and its blind faith in science, should be rejected. Yet for some this is not enough. They see the arguments against physicalism are devastating. But they are not willing to accept Substance Dualism. So they construct a “half-way house” between the two, hoping to save some of the Enlightenment Physicalism without all the problems discussed above. I think it also fails. Next week I’ll unpack this view and discuss where it goes wrong.

Until then, grace and peace.

For further reading I suggest Philosophical Foundations For A Christian Worldview by J.P. Moreland and William Lane Craig; Chapter 3: “Knowledge and Rationality,” Chapter 15: “Scientific Methodology” and Chapter 16: “The Realism-AntiRealism Debate”