In his recent book Faith, Science and Understanding, the physicist-turned-Anglican priest John Polkinghorne makes the claim that, in practice at least, “almost all scientists” are, philosophically speaking, critical realists. A reviewer in this magazine questioned that claim (Facing up to the mystery of God). “Where,” he wondered, “are the statistics?” The reviewer might then have added: “What does Polkinghorne mean by critical realism?” and “What difference does it make?”

It is no surprise that there aren’t statistics on the philosophical commitments of scientists. Many physicists, I think, would claim that the objects in their field of study are really only described, and can only be referred to, by the language of mathematics, and they would regard any attempt to discuss their fundamental properties using ordinary language as hopeless.

Many philosophers would hold that philosophy and science are such vastly different activities that it would be nonsensical to say that scientists “have” a philosophy of science at all. A person who engages in an activity does not need to have a good theory of it. “To expect a scientist to do philosophy of science,” the philosopher Imre Lakatos liked to remark, “is like expecting a fish to do hydrodynamics.”

However, I’d reject that analogy. Unlike hydrologists and fish, scientists and philosophers are both human beings; in principle each could do what the other does. More importantly, scientists have implicit conceptions of what they’re doing and of the kind of things they work with. It therefore seems reasonable to me to survey scientists regarding what they believe about those things, and to ask them what they consider real.

For what philosophers do is analyse such conceptions critically. They look for inconsistencies and contradictions, and they see if these views can be made consonant with other positions we hold about the world. Philosophers know that ideas about things are what physicists call “strongly coupled”. In other words, if you make what looks to be a small adjustment here, it can have a huge impact over there.

This is why philosophers go to such lengths to work through the details of such positions – to which they give various terms, such as “critical realism” – and debate the relative merits of each. This is also why a fully consistent philosophy of science is apt to look strange and unnecessary to scientists, who do not need to go to such lengths to get on with their work.

A survey could, therefore, be an important, if very informal, indicator of which of these positions ring truest for scientists.

So let’s generate some statistics. Below you will find a questionnaire – similar in format to those that some of my colleagues use in their surveys. It would bias the data if I simply listed the names of some philosophical positions – even with short descriptions – because your responses would be influenced by your prior assumptions about the positions or by my descriptions. Therefore the survey concerns what you consider to be “real things”.

The critical point

In a future column, I shall discuss the results, relate them to different philosophical positions, report whether Polkinghorne was right or not, and say what difference it makes.

It sounds easy to answer the question whether a thing is “real” or not. However, I’m sure that some people will find reason to object that, in some cases at least, the question is ambiguous or poorly formed. That’s partly the point. Teachers know the value of asking an ambiguous or poorly formed question as a way of eliciting a more informed understanding.

In the event that I get low statistics, there could be two possible explanations. Either nobody reads this column, which is totally unthinkable and can be dismissed out of hand, or scientists simply don’t care about these issues, which would be an interesting result in itself.

Readers’ poll

Listed below are some names that one often hears scientists mention. Your task is to consider whether they refer to real things. Write down in the first column (I) those that you would (y), would not (n) or are unsure (?) whether to consider real things. In the second column (P), indicate (with y, n or ?) what you think the average professional physicist would think. Finally, in the third column (C) indicate (with y, n or ?) what you think the average citizen would think.

 

The real thing?	I y/n/?	P y/n/?	C y/n/?
The Earth
Stones
Colours
Wavelengths
After-images
Hallucinations
Emotions
Genes
Atoms
The Bohr atom
Excited states of atoms
Electrons
Quarks
Higher-order infinities
Light waves
Viscosity
Kinetic energy
Electrical resistance
G (gravitational constant)
Real numbers
Mass
Imaginary numbers
Phlogiston
The Ptolemaic solar system
The Copernican solar system
Wavefunction (state of system)
Direction of time
Optional: why did you make the choices you did?

Answers can be sent by post to Robert P Crease at the address below, or by fax to +1 631 632 7522. You can also enter your responses electronically via the Brookhaven National Laboratory Web site.