Scientific Terms Can Obfuscate, Not Enlighten
When scientists classify things and use scientific terms, are they really shedding light on nature and natural history? It’s possible they may just be glossing over their own ignorance, suggested three articles in Nature last week. They underscore cases where subjective human conventions are falsely assumed to correlate with external realities. They lead us to ask, what do we mean by meaning?
- Words demean things: Apparently the editors of Nature have had it with certain clich�s. One editorial, published also on Nature News, pointed out the ambiguity of popular words and phrases used in scientific papers and by science reporters. The editorial began,
To a great extent, science is about arriving at definitions. What is a man? What is a number? Questions such as these require substantial inquiry. But where science is supposed to be precise and measured, definitions can be frustratingly vague and variable.
As examples, the editorial reviewed the terms paradigm shift, tipping point, race, epigenetic, complexity, stem cell, consciousness and significant. Those terms may seem intuitively obvious but in fact have multiple definitions. For the word consciousness to have meaning, for instance, there must be a physical basis for it – but none has been found. And significant is in the eye of the beholder, despite mathematical crutches like p-values that lend a false air of confidence in scientific results. Scientists often use a 5% confidence level as a measure of significance. That number, though, is an arbitrary convention – and often a useless one:
Even if a result is a genuinely statistically significant one, it can be virtually meaningless in the real world. A new cancer treatment may ‘significantly’ extend life by a month, but many terminally ill patients would not consider that outcome significant. A scientific finding may be ‘significant’ without having any major impact on a field; conversely, the significance of a discovery might not become apparent until years after it is made. “One has to reserve for history the judgement of whether something is significant with a capital S,” says Steven Block, a biophysicist at Stanford University in California.
- Class warfare: What do we mean by a class of objects? Take terms like species and planet: which objects belong in the class, and which are excluded? It’s not always easy to decide, said Jeffrey Parson and Yair Wand in an essay in last week’s Nature.1 The authors illustrate problems with these two examples. Look at the conflict over Pluto: is it a planet, a minor planet, or a plutoid? Depending on which properties of objects in space are considered useful to humans, it could be any one of these things – yet Pluto itself hasn’t changed. “Plutoid” is a recently made-up word about a class of objects of which Pluto is the best-known example. Just because the International Astronomical Union declares that from henceforth and forevermore Pluto is a plutoid, that does little more than provide a consensus for human beings and their nomenclature. Similarly, the term species contains considerable uncertainty, as even Ernst Mayr realized when he tried to define a species as a class of organisms that can produce fertile offspring (the “biological species concept”). Too bad that doesn’t work for the vast majority of organisms – asexual microbes and fossils.
Some classifications can lead to false and even fatal results. Consider the word disease, which originally just meant discomfort – or “not at ease.” The classification of diseases has usually been centered on etiology, or causes of disease. These fall into 3 subclasses: genetic, environmental or pathogenic. For nearly 40 years, the authors said, doctors misdiagnosed ulcers because they could not bring themselves to believe that a bacterium, H. pylori was capable of living in the acidic environment of the stomach. “When considering the reasons why the bacterial hypothesis was missed for such a long time (and then not readily accepted), the main problem was the misattribution of the property ‘cannot grow in the acidity of the stomach’ to the class of bacteria,” they explained. “Re-evaluating this fundamental property involved a major mind-shift that was difficult to accept.”
Classification is a human enterprise. The authors gave an evolutionary spin on this skill: “Classification … is recognized as an evolved mechanism that supports survival.” Supposedly it helps humans get food and shelter. They did not ask whether lions and lizards needed to evolve the mechanism to sort out their food and shelter, too. They tried to distinguish between “categories” and “classes” by defining the former as a group of objects with shared properties, and the latter as a category that allows humans to “infer further information” consistently “over a reasonable time period.” A little reflection, however, shows that they have simply substituted the word class for a meta-category with the same difficulties. The information that can be inferred from a class is simply a collection of objects with shared properties – things that humans find useful. Their final paragraph, though, revealed that they are aware of the main pitfall of classification: it happens in the mind, not in the external world.
Taking a classification perspective on scientific discourse suggests a sequence of questions to ask when studying a domain of phenomena. What are the properties of interest of these phenomena? Are there stable sets of properties common to these phenomena? Are there stable relationships in some of these sets? And finally, and most importantly, what is the evidence or rationale that these relationships reflect the true nature of the phenomena? This perspective has two important implications. First, scientists should make every effort to ensure that the assumed relationships among properties are indeed correct. Second, rather than arguing over which of several classification schemes is preferable, researchers should recognize that several correct and useful schemes can coexist. And overall, scientists should recognize that classification happens in the mind and, as a result, it can be influenced by beliefs and emotions. This is where science can go astray.
- The human element: The lead editorial in Nature last week brought these lessons home to the human species. What does it mean to be human? the editors asked.2 The Delphic oracle may have advised Know thyself, but that is often hard to follow, they said. Watch the editors balance their confidence in Darwin’s ability to help us know ourselves with doubts about the evidence:
Modern science can help, but using it to uncover truths about ourselves can also be fraught with difficulty. Consider, for example, that an important first step towards understanding contemporary human behaviour – establishing the evolutionary context in which it emerged – means piecing together odd scraps of evidence left by our hunter-gatherer ancestors tens of thousands of years ago. The paucity of data makes it all too easy to come up with untested, and even untestable, Darwinian versions of Rudyard Kipling’s Just So Stories.
After acknowledging that science’s just-so chickens have come home to roost, the editors resurrected an old conflict that illustrates the impossibility of speaking objectively about ourselves without wandering into politics:
Another major challenge for researchers is being objective about a topic as philosophically, politically and ethically charged as human nature. Take the sociobiology wars of the 1970s and 1980s. Left-wing scholars rejected biological explanations for phenomena such as gender roles, religion, homosexuality and xenophobia, largely because they feared such explanations would be used to justify a continuation of existing inequalities on genetic grounds. The resulting debates became hugely political.
The combustibility of the interface between science and society is one major reason for the extraordinary fragmentation of research that tackles human behaviour. In part because of the sociobiology battle, most social scientists still steer clear of using evolutionary hypotheses. And even researchers who do work under the unifying framework of evolution tend to fall into distinct camps such as gene-culture co-evolution or human behavioural ecology – their practitioners divided by differences of opinion on, say, the relative importance of culture versus genes.
The editors clearly think that evolutionary theory deserves to be a unifying theme, but have just cast doubt on the evidence behind it and the pragmatics of using it. They attribute the problems to the complexity of our species and the lack of interdisciplinary communication. In a belief that their magazine can help, they said they are starting a series of essays which, though they might make for “uncomfortable reading,” will try to draw lines between human evolutionary prehistory and the complex societies we live in. The first was by Pascal Boyer about the evolution of religion. Did it accomplish its purpose? See our review in the 10/26/2008 entry.
1. Jeffrey Parson and Yair Wand, “A question of class,” Nature 455, 1040-1041 (23 October 2008) | doi:10.1038/4551040a.
2. Editorial, “A look within,” Nature 455, 1007-1008 (23 October 2008) | doi:10.1038/4551007b.
It was good for Nature to point out these problems with scientific terminology. Unfortunately, their brains are so completely sold out to Darwin they are incapable of looking in the mirror. That’s why one moment they can be admitting the evidence is so scanty it gives ease to untested, untestable Just-So Stories about human evolution, then the next moment they give their editorial blessing to a stupid Just-So Story about the evolution of religion (10/26/2008).
Philosophy of science is a vital topic for anyone interested in science or apologetics or both. In philosophy of science you learn to ask questions that scientists themselves rarely ask. Consider the important topic of classification, brought up in bullet 2 above. Scientists too flippantly invoke class terms that are totally subjective when scrutinized. For instance, what is a predator? We think we understand the term, but in the class of predators you can find snails, tigers, and even the Venus Flytrap. The differences between these objects in the class predator seem more significant than the property they share: that they eat animals. In addition, each object belongs to multiple other classes that either distinguish it or include it: organism, vertebrate or invertebrate, plant or animal. The class you focus on is the one that is useful at the moment. If you are playing “Twenty Questions,” for instance, the categories initially useful to you are animal, vegetable or mineral, where animal could be anything from a flatworm to a giraffe, vegetable could be anything from algae to a redwood tree, and mineral could include diamonds and space stations. A corollary of this idea is that classes are merely human constructs – not necessarily ways of dividing up the world as it really is, or as Plato is said to have worded it, “carving nature at its joints.”
In his excellent lecture series on philosophy of science for The Teaching Company, Jeffrey L. Kasser used a humorous illustration. He invented a word broccosaxodile, which he defined as “anything that is broccoli, a saxophone, or a crocodile.” While one might question the usefulness of such a composite classification, he asked if it is any less meaningful than predator which, as we said, includes things just as diverse. “Predator” is just a shorthand word for a composite category that we could just as well call a “snail-tiger-VenusFlytrap.” Let’s add another example: what is a fossil? If you immediately picture bones in rock, you are ignoring the fact that fossils can include whole insects in amber complete with their soft tissue, footprints, petrified wood, and mere impressions of jellyfish or leaves, like shadows, without any bones at all. Fossils are not permanent, either: the dinosaur trackways in the entry below (10/28/2008) are eroding and will eventually disappear. In that sense, a corpse in a morgue is a fossil, or the ashes of a cremated person sitting in a bottle in the heartbroken spouse’s bedroom. (Not to be morbid, but it is almost Halloween.)
A classification is meaningless without a context in which the term is useful to some human being for a subjective purpose. There is nothing objective about a class if you want to think of it as referring to something that is “out there” in the world which scientists “discover” without bias. This should be a lesson to evolutionists who think they are talking objectively when they use class terms like missing link, transitional form, ancestors, phylogenetic tree, homologous traits or innovation. Such terms are employed for their utility – in this case, the utility of making evolutionary theory appear scientific.
Application. Let’s apply what we’ve learned to a Biblical example some find embarrassing. Many skeptics have ridiculed the Bible for classifying bats with birds in Leviticus 11:13-19 (see EvidentCreation.com). OK, their point is? This classification was amply useful to Moses, who was helping the Israelites distinguish what they were allowed to eat. The property apropos to their circumstances was clean and unclean edible animals. Moses, or God for that matter, was under no obligation to use modern scientific taxonomy for the purpose. In fact, it would seem much more helpful to Israelites wandering in the wilderness to point out which of those things flying around in the dark was safe to eat. Those of you who have camped in the desert know that swifts and bats can look very similar in the way they dart about. Formally, we can say that the property at issue in the class being defined was “flying things” – call them “volant vertebrates” if it makes you feel better – not whether the things had fur or feathers or laid eggs. Moreover, it would be an unfair disparagement of the mental capabilities of people who grew up in the advanced Egyptian civilization and their well-educated leader to assume they didn’t know the difference between birds and bats. We mustn’t be chauvinistic. They probably possessed more savvy about nature than the typical modern couch potato.
Exercise. Teachers and home-school parents: here is an opportunity to introduce your precocious young thinkers to some philosophy of science. Have them invent categories similar to broccosaxodile (above) and make lists of objects that fit. Is the category useful in some way? Does it allow inferring additional information? Which members belong to other categories?
Silly categories: Make up your own silly category and defend its usefulness: vege-toy-mobiles, dirt-bike-chocolate, sister-TV-cotton (anything that is either a sister, a television, or made of cotton), etc.
Trivial categories: Round things, small potatoes, friends, food, containers, pets, creeping things, rhyming words, oxymorons, shapes, etc. Think of more. In what circumstances are these useful categories? What are examples of extremely different things that can fit in the same category? Can you dream up a story to explain how the category evolved?
Scientific categories: omnivore, migratory species, gene, hybrid, moon, cloud, field, particle, wave, force, reagent, network, factor, family, biome, ecosystem, riparian dweller, marine invertebrate, intelligent life, sentient being. List some extremely different objects that fit into the same category. Pick an object in the category and list what other categories it belongs to. How well does the category reflect distinctions in the external world? What kinds of observations are required to make the distinction? Who does the observing? When is the category useful and not useful? Are the evolutionary stories told about these classes the only possible ways to understand them? What does “understanding” mean without the preconditions of immaterial concepts, reason, truth, and mind?