It just doesn’t matter very much—certainly not enough to keep wrangling over the exact definition of the boundary. As long as we understand what we mean by crystal, bacterium, RNA, etc., why should we care about the fuzzy dividing line? Are ribozymes going to become more or less precious to us according only to whether we count them as living or not, given that nothing changes about their actual manifested qualities? Should they?
Every science uses terms which are called universal terms, such as ‘energy’, ‘velocity’, ‘carbon’, ‘whiteness’, ‘evolution’, ‘justice’, ‘state’, ‘humanity’. These are distinct from the sort of terms which we call singular terms or individual concepts, like ‘Alexander the Great’, ‘Halley’s Comet’, ‘The First World War’. Such terms as these are proper names, labels attached by convention to the individual things denoted by them.
[...] The school of thinkers whom I propose to call methodological essentialists was founded by Aristotle, who taught that scientific research must penetrate to the essence of things in order to explain them. Methodological essentialists are inclined to formulate scientific questions in such terms as ‘what is matter?’ or ‘what is force?’ or ‘what is justice?’ and they believe that a penetrating answer to such questions, revealing the real or essential meaning of these terms and thereby the real or true nature of the essences denoted by them, is at least a necessary prerequisite of scientific research, if not its main task. Methodological nominalists, as opposed to this, would put their problems in such terms as ‘how does this piece of matter behave?’ or ‘how does it move in the presence of other bodies?’ For methodological nominalists hold that the task of science is only to describe how things behave, and suggest that this is to be done by freely introducing new terms wherever necessary, or by re-defining old terms wherever convenient while cheerfully neglecting their original meaning. For they regard words merely as useful instruments of description.
Most people will admit that methodological nominalism has been victorious in the natural sciences. Physics does not inquire, for instance, into the essence of atoms or of light, but it uses these terms with great freedom to explain and describe certain physical observations, and also as names of certain important and complicated physical structures. So it is with biology. Philosophers may demand from biologists the solution of such problems as ‘what is life?’ or ‘what is evolution?’ and at times some biologists may feel inclined to meet such demands. Nevertheless, scientific biology deals on the whole with different problems, and adopts explanatory and descriptive methods very similar to those used in physics.
The quote says that biologists don’t deal with questions such as “what is life?” because that’s essentialism and that’s Bad. Similarly, physicists certainly don’t study ideal systems like atoms or light. The disease is in the false dichotomy.
Oh, hmm, I thought what he was saying about atoms and light is not that physicists don’t study those things, but that they don’t study some abstract platonic version of light or atom derived from our intuitions, but instead use those words to describe phenomena in the real world and then go on to continue investigating those phenomena on their own terms.
So, for example, “Do radio waves really count as light?” is not a very interesting question from a physics perspective once you grant that both radio waves and visible light are on the same electromagnetic wave spectrum. Or with atoms we could ask, “Are atoms really atoms if they can be broken down into constituent parts?” These would just be questions about human definitions and intuitions rather than about the phenomena themselves. And so it is with the question, “What is life?”
That’s what it seemed like Popper was saying to me. Did you have a different interpretation? Also, I’m not sure I’ve understood your comment—which dichotomy are you saying is a false dichotomy?
Asking whether radio waves really count as light is just arguing a definition. That’s not interesting to anyone who understands the underlying physics.
Notice that the questions he gives for essentialists are actually interesting questions, they’re just imprecisely phrased, e.g. “what is matter?” These questions were asked before we’d decided matter was atoms. They were valid questions and serious scientists treated them. Now these questions are silly because we’ve already solved them and moved on to deeper questions, like “where do these masses come from?” and “how will the universe end?”
When a theorist comes up with a new theory they are usually trying to answer one of these essentialist questions. “What is it about antimatter that makes it so rare?” The theorist comes up with a guess, computes some results, spends a year processing LHC data, and realizes that their theory is wrong. At some point in here they switched from essentialist (considering an ideal model) to nominalist (experimental data), but the whole distinction is unnecessary.
… they don’t study some abstract platonic version of light or atom derived from our intuitions …
Yes, they most certainly do. QED is an extremely abstract idea, derived from intuition about how the light we interact with on a classical level behaves. This is called the correspondence principle.
String theorists come up with a theory based entirely on mathematical beauty, much like Plato.
I think you’re reading Popper uncharitably, and his view of what physicists do is about the same as yours. He really is arguing against arguing definitions. “What is matter?” is an ambiguous question: it can be understood as asking about a definition, “what do we understand by the word ‘matter’, exactly?”, and it can be understood as asking about the structure, “what are these things that we call matter really made of, how do they behave, what are their properties, etc.?”. The former, to Popper, is an essentialist question; the latter is not.
Your understanding of “essentialist questions” is not that of Popper; he wouldn’t agree with you, I’m sure, that “What is it about antimatter that makes it so rare?” is an essentialist question. “Essentialist” doesn’t mean, in his treatment, “having nothing to do with experimental data” (even though he was very concerned with the value of experimental data and would have disagreed with some of modern theoretical physics in that respect). A claim which turns out to be unfalsifiable is anathema to Popper, but it is not necessarily an “essentialist” claim.
Oh, hmm. I see now that we were interpreting Popper differently, and I may have been wrong.
Notice that the questions he gives for essentialists are actually interesting questions, they’re just imprecisely phrased, e.g. “what is matter?” These questions were asked before we’d decided matter was atoms. They were valid questions and serious scientists treated them. Now these questions are silly because we’ve already solved them and moved on to deeper questions …
If Popper did mean to exclude that kind of inquiry, then I agree with you that he was misguided.
In that case, it sounds like you would agree with the rest of Anatoly’s comment, just not the Popper quote. Is that right?
The precise definition of life will not be the thing that will determine our opinion about possible extraterrestrial life when we come across it. It will matter whether that hypothetical life is capable of growth, change, producing offspring, heredity, communication, intelligence, etc. etc. - all of these things will matter a lot. Having a very specific subset of these enshrined as “the definition of life” will not matter. This is what Popper’s quote is all about.
The precise definition of life will not be the thing that will determine our opinion about possible extraterrestrial life when we come across it.
It’s possible that extraterrestrial life will be nothing but a soup of RNA molecules. If we visit a planet while its life is still in the embryonic stages, we need to include that in our discourse of life in general. We need to have a word to represent what we are talking about when we talk about it. That’s the only purpose any definition ever serves. If you want to go down the route of ‘the definition of life is useless’, you might as well just say ‘all definitions are useless’.
It just doesn’t matter very much—certainly not enough to keep wrangling over the exact definition of the boundary. As long as we understand what we mean by crystal, bacterium, RNA, etc., why should we care about the fuzzy dividing line? Are ribozymes going to become more or less precious to us according only to whether we count them as living or not, given that nothing changes about their actual manifested qualities? Should they?
-- Karl Popper, from The Poverty of Historicism
Why did you post this quote? It seems like a good example of diseased thinking, but I’m not sure if that was your point.
Are you saying you think the quote exhibits diseased thinking or just that it was about diseased thinking?
To me, the quote seemed to clearly make the same point that Anatoly’s first paragraph did, so it seems straightforward why he would include it.
The quote says that biologists don’t deal with questions such as “what is life?” because that’s essentialism and that’s Bad. Similarly, physicists certainly don’t study ideal systems like atoms or light. The disease is in the false dichotomy.
Oh, hmm, I thought what he was saying about atoms and light is not that physicists don’t study those things, but that they don’t study some abstract platonic version of light or atom derived from our intuitions, but instead use those words to describe phenomena in the real world and then go on to continue investigating those phenomena on their own terms.
So, for example, “Do radio waves really count as light?” is not a very interesting question from a physics perspective once you grant that both radio waves and visible light are on the same electromagnetic wave spectrum. Or with atoms we could ask, “Are atoms really atoms if they can be broken down into constituent parts?” These would just be questions about human definitions and intuitions rather than about the phenomena themselves. And so it is with the question, “What is life?”
That’s what it seemed like Popper was saying to me. Did you have a different interpretation? Also, I’m not sure I’ve understood your comment—which dichotomy are you saying is a false dichotomy?
Asking whether radio waves really count as light is just arguing a definition. That’s not interesting to anyone who understands the underlying physics.
Notice that the questions he gives for essentialists are actually interesting questions, they’re just imprecisely phrased, e.g. “what is matter?” These questions were asked before we’d decided matter was atoms. They were valid questions and serious scientists treated them. Now these questions are silly because we’ve already solved them and moved on to deeper questions, like “where do these masses come from?” and “how will the universe end?”
When a theorist comes up with a new theory they are usually trying to answer one of these essentialist questions. “What is it about antimatter that makes it so rare?” The theorist comes up with a guess, computes some results, spends a year processing LHC data, and realizes that their theory is wrong. At some point in here they switched from essentialist (considering an ideal model) to nominalist (experimental data), but the whole distinction is unnecessary.
Yes, they most certainly do. QED is an extremely abstract idea, derived from intuition about how the light we interact with on a classical level behaves. This is called the correspondence principle.
String theorists come up with a theory based entirely on mathematical beauty, much like Plato.
I think you’re reading Popper uncharitably, and his view of what physicists do is about the same as yours. He really is arguing against arguing definitions. “What is matter?” is an ambiguous question: it can be understood as asking about a definition, “what do we understand by the word ‘matter’, exactly?”, and it can be understood as asking about the structure, “what are these things that we call matter really made of, how do they behave, what are their properties, etc.?”. The former, to Popper, is an essentialist question; the latter is not.
Your understanding of “essentialist questions” is not that of Popper; he wouldn’t agree with you, I’m sure, that “What is it about antimatter that makes it so rare?” is an essentialist question. “Essentialist” doesn’t mean, in his treatment, “having nothing to do with experimental data” (even though he was very concerned with the value of experimental data and would have disagreed with some of modern theoretical physics in that respect). A claim which turns out to be unfalsifiable is anathema to Popper, but it is not necessarily an “essentialist” claim.
Oh, hmm. I see now that we were interpreting Popper differently, and I may have been wrong.
If Popper did mean to exclude that kind of inquiry, then I agree with you that he was misguided.
In that case, it sounds like you would agree with the rest of Anatoly’s comment, just not the Popper quote. Is that right?
That’s right, more or less.
Gotcha, thanks!
Which disease are you referring to?
“Diseased thinking” here is probably jargon; see Yvain’s 2010 post “Diseased thinking: dissolving questions about disease”.
The definition of life matters because we want to be able to talk about extraterrestrial life as well.
The precise definition of life will not be the thing that will determine our opinion about possible extraterrestrial life when we come across it. It will matter whether that hypothetical life is capable of growth, change, producing offspring, heredity, communication, intelligence, etc. etc. - all of these things will matter a lot. Having a very specific subset of these enshrined as “the definition of life” will not matter. This is what Popper’s quote is all about.
It’s possible that extraterrestrial life will be nothing but a soup of RNA molecules. If we visit a planet while its life is still in the embryonic stages, we need to include that in our discourse of life in general. We need to have a word to represent what we are talking about when we talk about it. That’s the only purpose any definition ever serves. If you want to go down the route of ‘the definition of life is useless’, you might as well just say ‘all definitions are useless’.