I see this term every time I read an introductory science textbook (be it psychology, chemistry, physics, biology, astronomy), and at the beginning where they ask “what is science?”, they sometimes include “just a theory”.
What is the origin of this phrase, “just a theory”? Does this phrase imply that the average person not learned in science naturally going to think that a ‘theory’ is a subjective thought?
I don’t know… but every time I read the phrase, I think the textbook is trying to inform the unscientific public the meaning of ‘theory’ in the scientic realm, as if the unscientific public really use the word ‘theory’ in some other sense of the term.
That said, is it ok that I say, “I think the car is running out of gas. But that’s my theory.”? Or should I say, “I think the car is running out of gas. But that’s my hypothesis.”?
A “theory” is more than a hypothesis - it’s a framework, not just a single point of fact. More importantly it is one that is still being worked out: the book is still open, so to speak. It has not been disproven with a counterexample (which would kill it right there), but is also not 100% ironclad proven with an a priori proof.
Sometimes you have two competing theories on how something works, for example, which both cover all the known data, and people get to argue about it until such time as one or the other of them is conclusively proven or disproven. This is especially true for fields where even what constitutes valid data is up for argument, like world economic models. Or, certain models of the universe in modern physics such as the “Many Worlds Theory” or “String Theory” that are essentially untestable and hence unfalsifiable (as the famous physicist Pauli once commented on a paper, saying “this not only isn’t right, it’s not even wrong”). Or even whether the Sun revolves around the Earth or the other way around, a brouhaha which Galileo Galilei was famously involved in. Today we often learn that Galileo “knew” he was right, but the geocentric model against which he was arguing actually would not be conclusively disproven (based on stellar parallax) until technology in the 19th Century made such observation possible.
Saying something is “just” a theory is pretty stupid though - those who say it usually do so as if all non 100% logically iron-clad statements are equally invalid, which is obviously not the case. For example the “Evolution of Man” is not “just” a theory - it has a lot lot lot of evidence behind it, as well as testable and reproducible evidence of the evolutionary process happening with other species. Yes, you CAN point out that another theory, such as Intelligent Design, can incorporate all the same data yet operate on a different premise for the origin of observable life on Earth today. Or for all you know, that space aliens created and seeded the entire planet shortly before your birth with the sole intent of seeing how you would develop, like in The Truman Show but on a far larger scale. How would you know? But these theories are not all equally reasonable.
I really do not think you have answered my question. I asked for the origin or history of the phrase, if it had one, not a long-winded argument what it is. :smack:
I largely suspect that the phrase is related to anti-evolution movement in the United States that started in the mid-20th century and sought to ban evolution in public schools, and even though it was successful early in its career, the public somehow became more informed about science, and the anti-evolution movement became weaker and sank into oblivion. Perhaps, the definition of “science” rose then, because of that moment in history. And every single science-related textbook sought to define science, in the way that scientists would think of them.
I did a quick search, and pretty much everything I turned up related to evolution, for instance this.Here is a book.
I have a hard time believing that a legitimate science textbook would use the phrase “jst a theory” except ironically (and there is precious little space for irony these days.) “Just” is clearly denigrating. So my guess would be that its origin is during the creationist resurgence you mentioned, but that is just a guess.
I wish I could be as optimistic as you. The courts have been good at keeping creationism out of the schools, but they are still out there, as the Republican debates clearly demonstrated.
The fact is that in ordinary usage, including amongst scientists, “theory”, like many words, occurs in more than one (related but not identical) sense. Sometimes it is used to mean what robardin says. Sometimes it is used to mean hypothesis, or even just an educated guess. These are all perfectly correct usages.
The problem with this is that in relatively recent times, politically motivated anti-science creationists have popularized a fallacious but (to the gullible or careless) superficially appealing argument against evolution that works by equivocating on these different senses of the word “theory”. They note that scientists commonly (and properly) refer to as the theory of evolution, and then draw (or attempt to gull others into drawing) the fallacious conclusion that this means (that scientists really know that) it is “just a theory” in the sense of being a hypothesis or guess, and thus does not deserve to be taken too seriously.
Of course, the truth is that when scientists refer to the “theory of evolution” they do not mean “theory” in the sense of hypothesis or guess, but in the much more substantial sense so well outlined by robardin. The argument is a rhetorical trick, but the forces of anti-enlightenment have got a lot of mileage out of it.
Because of that, some of those who wish to defend the scientific world view (such as the writers of science textbooks) have probably become rather hypersensitive about this argument, and are anxious (perhaps overanxious) to immunize students against the temptations of this fallacious argument by making sure that they are well aware of the fact that use of the word in its much stronger sense (robardin’s sense) is common in science. Presumably that is why you are finding this sort of definition made very explicit and placed front and center in a lot of recent science textbooks. Furthermore, given the pressures on textbook writers to oversimplify things, I would not be at all surprised if a lot of these textbook discussions of “theory” (falsely) say or imply that this is the only sense in which the word “theory” is used by scientists.
Anyway, to sum up: although those words have probably been used in that order (and without intent to mislead) by other people before, the phrase has fairly recently been popularized by anti-science creationists as part of their broader disinformation campaign, and it (presumably) appears in recent textbooks as part of an attempt to preempt or counter, in students’ minds, the potentially very pernicious effects of the fallacious and dishonest creationist argument that feature it on the students’ understanding of evolution (and potentially other areas of science too, although they are more in the way of collateral damage sustained in the course of the main campaign against evolution, which is itself is ultimately part of a campaign to turn back the social changes of the last several decades).
“Theory” in this case stands in contrast to “Law”… Even the Road Runner knew about the Law of Gravity, even if he didn’t study it. I recall grade school science classes (Catholic school, Wisconsin, hardly a hotbed of anti-evolution thinking then or even now) presenting “Laws” as being something firmer than “Theories” as they were introducing us kids to the scientific method… furthermore, the distinctions between “Theories” and “Hypotheses” weren’t made as well they could have, I think. Thus you leave kids who grow up with the idea that a “Theory” implies major caveats of doubt.
A quick search of Google Books turns up a couple of instances of “just a theory” being used in this sense* in the late 19th century. From an 1894 issue of the Glasgow Medical Journal: “Dr. Newman had explained the death as due to ‘delayed shock’. Dr. Steven thought that that was just a theory and he himself would attach more importance to the indications he had found in the body…”
*There are more hits from that period where a theory is described as “just” in the sense of being fair, in phrases like “No matter how just a theory may be…”
As has been noted the phrase “just a theory” as a unit has become a rhetorical device with a significant pegorative component. The word “just” being the key. Asking where this particular use comes from will usually be rooted in creationism. As noted above, it comes from a general misunderstanding of what science is, and what a theory is. I blame trashy detective novels with popularising this misunderstanding. When some Sherlock wannabe says “my theory is that the butler did it” he isn’t espousing a theory in the form a scientist would recognise. Hypothesis yes, theory no. Even possibly a falsifiable hypothesis. A mathematician as an even more rigorous understanding of theory, requiring it to be derivable from axioms.
