Science: universal or useful?
It can’t be both.
In the Enlightenment vision of science that we discussed in Re-Assembling Reality #5, people demand (or expect, or at least hope) that science be universal. Scientific statements should hold for all people, at all times, in all places. Anything that falls short of this does not deserve the accolade of being called “science.”
It is reasonably clear that science can make universal statements. Consider the statement, “hydrogen atoms are neutral.” You can pass on this information, knowing that it holds for all people, at all times, in all places. You can take a 13-billion-year-old hydrogen atom from interstellar gas, or a newly minted hydrogen atom you found in your cornflakes; they will both be neutral. You can give a hydrogen atom to your grandma with the message “this hydrogen atom is neutral”, or you can seal it in a vault for a billion years with a message for the race of dog-people which may evolve after humanity’s extinction. The statement is true for all people, at all times, in all places. It is universal.
So science can make universal statements. But does it have to? Could it make particular statements if it wanted to?
Consider the statement, “This chocolate is toxic.” Before handing such a bar over to your grandma, you may justifiably ask, “For whom is it toxic?” If it is normal store-bought chocolate, it is probably not toxic for your grandma, or indeed for you. It is, however, toxic for your dog. It may well be toxic to hyper-evolved dog-people a billion years from now.
Toxins kill because they interfere with a particular biological mechanism. However, different organisms have different biologies. This is necessarily true, otherwise they wouldn’t be different organisms. People happily eat chocolate, though the methylxanthines it contains will kill your dog and your rabbit. By contrast, rabbits happily eat belladonna, though the atropine it contains will kill people and dogs. Peanuts will kill some people, but not others, and they most likely won’t kill your dog or your rabbit.
This lack of universality might seem to exclude toxicology from being a science. Nonetheless, there are other reasons for which we might want to count toxicology as a science. It certainly feels like a science. Toxicologists work in a lab and wear white coats. They write research papers that get published in scientific journals, and they get funding from science foundations. It seems to have all the trappings of a science.
Universality of statements
Can we rescue the situation by recasting toxicological statements in a universal form? We started with the back and forth, This is toxic — but toxic for whom? Can we solve the problem by simply answering the question? Belladonna is toxic for people and dogs. Done.
But wait! I have more questions.
Q: What about for the race of dog-people which may evolve after humanity’s extinction? Is it toxic for them?
A: Belladonna is toxic to any organism in which atropines disrupt the nervous system.
Q: What if it is genetically modified belladonna that doesn’t contain atropines?
A: Any substance which contains atropines is toxic to any organism in which atropines disrupt the nervous system.
Q: What if it doesn’t contain much? Or what if they only eat a little bit?
A: Any substance which contains atropines is toxic, in sufficiently high doses, to any organism in which atropines disrupt the nervous system.
Q: But what if the dog-people in the future have evolved a mechanism to temporarily shut down their central nervous system until the effect of the atropine wears off?
A: Any substance which contains atropines is toxic, in sufficiently high doses, to any organism in which atropines disrupt the nervous system, unless there are mechanisms to mitigate the effect.
Are we done? No. We found in our essay on Science and Method (Re-Assembling Reality #6) that the list of caveats that we would need to make would be infinitely long. So no, we are not done. If we have a finite amount of time, or a finite world limit on toxicological papers, we cannot — even in principle — make universal toxicological statements.
We should not feel too bad about this. In addition to such universal statements not being possible, they are not useful. Every additional caveat that we add to the statement to make it more universal makes it less helpful. Dropping the reference to “belladonna” in favour of “any substance which contains atropines” just prompts us to ask “Is belladonna such a substance?” Substituting “any organism in which atropines disrupt the nervous system” in place of “people and dogs” may make the statement more general and possibly more true, but it still prompts us to ask “Is my grandma such an organism?” Every step towards universalising the statement obscures the answer to the question about which we really care: can I give this to my grandma?
Beyond not being possible and not being helpful, it seems—in common practice — that making universal statements is not necessary for toxicology to be considered a science. As stated above, we want toxicology to count as a science. It feels like a science. Toxicologists can get papers accepted in scientific journals and, if they are rejected, it is not because they fail to make universal statements. Toxicologists can get money from scientific funding agencies and, if their proposals are rejected, it is not because their conclusions are unlikely to be universal.
Universality of methods
Should we roll over and accept defeat then? “The funding bodies have spoken: toxicology counts as science; the case is closed”? Or should we push back and insist that the funding bodies and journals are wrong to accept toxicology as a science? We should not be too hasty in accepting the funding agencies’ decision, as we have not yet exhausted the list of problems that are caused for universality when science is expanded to admit toxicology. We are not only forced to abandon universality in scientific statements. We may choose to abandon universality in scientific methods.
As an experimentalist, if I want to know whether a rock falls if I let go of it, there is a very simple way to find out: I let go of a rock, and I see if it falls.
As an experimentalist, if I want to know whether belladonna will kill me if I eat it, there is a very simple way to find out: I eat the belladonna and see if I die.
My personal involvement in this situation makes recording the results in my lab book difficult. I am pressed to find an alternative method. I could, for example, establish that my neurological responses are, broadly speaking, similar to those of some students. I could then dissect some of those students to establish that their biology was all reasonably consistent, and feed the rest of the students belladonna to see if they died. When they did die, and on the assumption that both I and they had a similar biological make-up to the students I dissected, I could infer that were I to eat belladonna, it would be toxic to me.
We established in Science and Method (Re-assembling Reality #6) that we do not follow the Popperian or Baconian scientific method. We left open, however, the hope that there could be some other method we might follow. We admitted that over time there had been multiple scientific methods, plural, but held out the hope that maybe, once we hit on the correct method, it would be singular and universal. We have now found that the direct method which physicists can follow (If I want to know what would happen if I drop this rock, then I drop this rock) is different from the indirect method that toxicologists must follow (If I want to know what would happen if I ate this belladonna, then I get someone else to eat the belladonna and extrapolate from that).
Admitting toxicology into science would mean accepting a multiplicity of methods, with different methods being selected for different problems, or when wanting to obtain different information. This would strike a hard blow indeed against universality in science.
Universality of questions
Our problems do not, however, stop there. Our Enlightenment vision of science (Re-Assembling Reality #5) insisted that the universality of science meant that science held for all questions, or at least all meaningful questions. Or at very least for all meaningful objective questions. Unfortunately, toxicology asks questions that cannot be asked by other sciences.
Let us consider, first, how to describe an expanding gas. If I compare a macroscopic description (which talks about pressure and volume and temperature) with a microscopic description (which talks about the number of particles and their velocities and momenta), the descriptions look very different. But both levels of description are able to account for what is happening with the expanding gas. All questions about pressure and volume can be recast into questions about velocity and momentum. There are no scientific ideas at the macroscopic scale which cannot be described and explained using the scientific ideas at the microscopic scale. This universality of description establishes physics as good science.
Let us contrast this happy situation with consideration of a toxin. A substance is toxic if it kills the organism concerned. To kill is to change the organism from the state of being alive to being not alive. There is no reductionistic correlate in physics to the concept of being alive. If physics has no way to talk about life, it cannot talk about death, and cannot talk about toxins. “Toxic” only becomes a meaningful concept in the life sciences. We either abandon the requirement of universality for science, or we throw out toxicology as a science, and for good measure throw out all life sciences.
Before rushing to throw out the life sciences, though, we might wish to pause and consider the symmetry of the situation. The argument from our Enlightenment vision runs as follows:
Science can answer all real questions. If physics is a science, and physics cannot talk about life, then questions about life are not real questions. Consequently toxicology, which needs to talk about life, doesn’t talk about real things. Toxicology is therefore not a real science.
This seems all very clear, and toxicology is rejected. What would we have done, however, if we had started our consideration from the other side?
Science can answer all real questions. If toxicology is a science, and toxicology talks about life, then questions about life are real questions. Consequently physics, which cannot talk about life, cannot answer all real questions. Physics is therefore not a real science.
This leaves us with two options:
Option 1) Either physics or toxicology is a science, but not both. And we do not have a good way to decide which it is. Or
Option 2) The Enlightenment vision of science is in trouble, and we must let go of science being universal.
Universality is doomed
The net is closing in. Each way we turn, universality seems imperiled. But our hand is not yet forced. However unappealing Option 1 might be, it is still an option. Let us hold to the ideal of universality for as long as we can, and follow where it leads.
We have tried to make the statements of toxicology universal. And in this we have failed. The contextual, contingent, shifting nature of toxicology means that it is not possible to derive it from the universal physical laws that underlie it, nor present it in a universal way. Not even in principle.
Against this, we find it hard to shake the feeling that the question “will this kill my grandma?” is an important question. It certainly seems meaningful. It also seems that the answer should be objective. Having eaten belladonna, my grandma will either die or she will not. I cannot turn round and say “Oh, she only thinks she’s dead.” Toxicology, therefore, seems to deal with meaningful objective questions.
We may choose to hold on to the Enlightenment vision’s insistence that scientific statements must be universal, and consequently accept that toxicology is outside the realm of science. This, however, would mean that there are meaningful, objective questions that are outside the realm of science. Science would therefore not be universal. At least not universal in scope. The enlightenment hope of universality has slipped.
Can we rescue the enlightenment hope that science is universal in scope; that it is able to address all meaningful, objective questions? Yes, at a price. We can admit that toxicology, which is able to answer the question “Will this kill my grandma?” is in fact a science. But then we must accept that there are validly scientific statements that are particular, not universal. Again the Enlightenment hope of universality has slipped.
Whichever way we slice it, we cannot save all aspects of universality. The question has moved from “Can we save universality?” to, at best, “Which bits of universality, if any, might we want to salvage?”
The significance of pragmatism
In order to answer that question, it is worth considering one of the key features of science. We have previously considered whether science needs to be explanatory, or predictive, or unifying (Re-Assembling Reality #7), and found that it may be none of these things. We have also found that science need not be methodological, or objective, or universal. We have hinted that it need not even be true.
Despite all this, science works. If you want to fly to the moon, you get on the rocket that science built. The connection between science and functioning technologies is not coincidental, but the causality does not work in the direction that is often assumed. People often think that a given theory works because it is scientific. In fact, it is much more likely that a given theory is considered scientific because it works.
Consider Isaac Newton. Newton did research on mechanics, gravity, and the transmutation of elements. His work on mechanics allowed people to predict where a cannonball would land, and it was counted as science. His work on gravity allowed people to account for the motion of the planets, and it was counted as science. His work on the transmutation of elements did not have the applications for which many people had hoped. This aspect of his work was considered to be occult, magical, certainly not scientific.
Newton’s work on mechanics said that F = ma. Einstein showed us that this is not strictly correct. Newton’s work on gravity said that space and time were an inert background on which things happened, and were unperturbed by gravity. Einstein showed us that this is not strictly correct. Newton’s work on transmutation said that chemical elements are not fixed, but can be interconverted from one to another. Einstein knew this to be correct and — in his objection to the development of nuclear weapons — knew it to be significant.
Time and again we see that if an idea is useful it is embraced as part of science, regardless of its truth (or falsity). Conversely, if it is not useful it is disbarred from science, regardless of its falsity (or truth).
Usefulness — for ideas, just as for objects — is context-dependent. A hammer is useful if you are faced with a nail, but not useful if you have a bolt. A spanner is useful when you have a bolt, but not so much when you have a nail. At a pinch, you can knock in a nail with a spanner, but you cannot tighten a bolt with a hammer. When faced with a tool kit, one cannot ask, “What is the right tool?” or even “What is a good tool?” without first knowing the task for which the tool will be used. There is no such thing as a universally useful tool.
In like manner, if you want to design an aeroplane wing, a scientific model that treats the atoms in the air as billiard balls is useful. A quantum model of the atoms would be useless for the task, if only because of the excessive computational power required to get any answers. By contrast, if you want to understand absorption spectra, a quantum model is useful while a billiard-ball model is utterly useless.
An adjustable spanner may be useful in more situations than a 12 mm spanner. You may even say an adjustable spanner is the closest thing in the toolbox to being “universally applicable.” That does not stop a 12 mm spanner from being a tool. And it also does not mean that you should choose to use the “more universal” adjustable spanner rather than a screwdriver when you are faced with a screw.
Different tasks require different tools. No tool is good for everything, and we select from our tool box a tool that will get the job done well. This is true of nails and shelves, as it is true of aeroplane wings and absorption spectra. If we view science as a box of tools, we should not be surprised that there are things which are appropriately considered part of science and which are not universal. If there is no universally useful tool, then pragmatism says that for science to be useful, it should also not be universal.
Are we OK with this?
Should any of this surprise us?
Arguably, it should not. We speak of sciences (plural): natural sciences, social sciences, medical sciences, engineering sciences; theoretical sciences, experimental sciences; physical sciences, life sciences. These sciences can use contradictory assumptions and reach contradictory conclusions. A biologist who considers a universe teeming with life is being no more or less scientific than a physicist who considers a lifeless world. Medical scientists accept two standard deviations as evidence of a discovery, while particle physicists insist on at least five. It is good physics to invoke the etiological frame of Newtonian mechanics, and it is also good physics to invoke the teleological frame of Lagrangian mechanics. Few scientists lose sleep over the fact that quantum mechanics and relativity are apparently irreconcilable. Those who even think about it tend to view it as an avenue for future scientific research, rather than cause to reject either as unscientific.
The abandonment of universality in science should therefore not surprise us. But are we OK with it? Should it concern us?
If good scientists can appropriately use contradictory assumptions and come to contradictory conclusions, and still be doing good science, then something very strange has happened to the relationship between science and truth. I can ask, “Is this hammer useful for the task at hand?” But I do not ask “Is this hammer truthful?” If science is like a tool kit — useful but not universal — what have we done with truth? And are we OK with that?
This will be considered in a future essay.
 Obviously, this is a hypothetical scenario. I have never and will never poison my students simply for the joy of scientific discovery. That would be wrong. And generate lots of paperwork.
This essay and the Re-Assembling Reality Medium series are brought to you by the University of Hong Kong’s Common Core Curriculum Course CCHU9061 Science and Religion: Questioning Truth, Knowledge and Life, with the support of the Faith and Science Collaborative Research Forum and the Asian Religious Connections research cluster of the Hong Kong Institute for the Humanities and Social Sciences.