Contra theologian Roger Trigg on the nature of science

Roger Trigg is a senior theologian and philosopher. His new book, “Beyond Matter”, is soon to be published by the Templeton Press, part of the wealthy Templeton Foundation whose aim is to produce a religion-friendly version of science.

An excert from the book promotes a view of science that is common among philosophers. Those of us with a scientistic perspective see it as erroneous, and yet, since Trigg’s account of science is widely accepted, it is instructive to rebut it.

Trigg argues that science rests on metaphysical assumptions:

What then has to be the case for genuine science as such to be possible? This is a question from outside science and is, by definition, a philosophical — even a metaphysical — question. Those who say that science can answer all questions are themselves standing outside science to make that claim. That is why naturalism — the modern version of materialism, seeing reality as defined by what is within reach of the sciences — becomes a metaphysical theory when it strays beyond methodology to talk of what can exist. Denying metaphysics and upholding materialism must itself be a move within metaphysics. It involves standing outside the practice of science and talking of its scope. The assertion that science can explain everything can never come from within science. It is always a statement about science.

This view can be summarised by the “linear” schematic:

One can see why theologians like this account of science. If it were really true that science rested on metaphysical assumptions then science would be in big trouble, since no-one has ever proposed a good way of validating metaphysical assumptions.

A scientism defence of Logical Positivism

Like everyone else I read Ayer’s Language, Truth and Logic as a teenager and, like many people of a scientific bent, I loved it. The Logical Positivism that it espoused can be summarised as the claim that knowledge is of two types: (1) logical reasoning from axioms, such as used by mathematics; and (2) claims about the universe that can (in principle) be verified empirically. Anything else — such as metaphysics — is literally meaningless.

Logical Positivism is generally held to have been refuted (following criticisms from notables such as Quine, Popper and others), and as stated in its original form that is a fair assessment. However, its general thrust can be defended as sound. Indeed, Logical Positivism was a forerunner of what today gets called scientism, and interpreting it as scientism it is very much alive.

First, a defender of scientism would subsume the first type of knowledge, the “logical reasoning from axioms”, into the knowledge that derives from empiricism and can be empirically verified. Afterall, the reason that we adopt our basic axioms of logic and mathematics is because they work — they give results that apply to our universe. Where else would we have got them from?

What does “existence” mean?

During a recent online discussion I discovered, somewhat to my surprise, that there is no general agreement on what the word “exist” means. Everyone has an intuitive understanding of it but when it comes to an explicit definition of the word there is no consensus, and indeed philosophers have written a vast literature on the topic of ontology, or what exists.

Dictionaries don’t really help; for example Oxford Dictionaries gives a nicely circular set of definitions:

Exist: 1. have objective reality or being
Reality: 1. the state of things as they actually exist
Being: 1. existence.

Of course physicists have a perfectly good operational definition: something exists if it is capable of making a detector go ping. Try arguing that, however, and you’re immediately accused of materialism, physicalism, scientism, being blind to possibilities beyond a very narrow world-view, and a host of similar sins (I plead guilty to at least the first three).

Scientism and questions science cannot answer

“Scientism” is often taken as the claim that science can answer all questions. Of course there are plenty of things that scientists don’t currently know, so the suggestion is, instead, that science could potentially answer all questions, or at least all meaningful questions.

For example the philosopher Julian Baggini says that

“What is disparagingly called scientism insists that, if a question isn’t amenable to scientific solution, it is not a serious question at all.”

Another noted philosopher, Massimo Pigliucci, writes in his book Nonsense on Stilts :

“The term “scientism” encapsulates the intellectual arrogance of some scientists who think that, given enough time and especially financial resources, science will be able to answer whatever meaningful question we may wish to pose …”

I disagree with these definitions (both of course by people critical of scientism), and suggest that scientism is instead the claim that science can answer all questions to which we can know the answer. The point is that there are many questions that are “meaningful”, yet we can never, even in principle, answer them. First let’s distinguish between meaningful and meaningless questions.

Can science attain truth? Why science is like golf

Scientific knowledge is provisional: it is founded on empirical evidence and our knowledge of empirical evidence will always be incomplete. Thus there is always the possibility of new evidence coming along to show that some area of scientific understanding is wrong.

This leads to a common claim that science can be disregarded because its ideas are always changing. For example, the fundamentalists at Answers in Genesis say:

We agree that scientists should continually refine their views as new information becomes available, but that is precisely the problem … Evolutionary scientists have changed “common knowledge” multiple times over the past century, yet the Bible has not changed. It still clearly teaches that the universe, earth, and dinosaurs were made during a six-day period about 4,000 years before Christ.

And the complaint isn’t only from Biblical literalists. Mark Vernon, a liberal “agnostic Christian” who used to be an Anglican priest, writes in the Guardian:

There are, of course, differences between scientific and religious myths. For one thing, scientific myths are far less long-lived than religious ones. The great faiths of the world daily turn to myths that are thousands of years old and find truth leaping off the page as they read them. Scientific myths, on the other hand, do well if they last more than a century. Who today reads Newton?

Is the complaint fair? To use an analogy, science is like golf, where the “hole” we are aiming for is truth, and by a “true” scientific theory we mean one that matches the empirical reality of our universe. Nature sets the lie of the golf course and the location of the hole, and science tries to find it. So we revise our theories when better empirical evidence comes along, and each time we do that we halve our distance to the hole.