What used to be considered pseudoscience by the scientific community but now isn’t?

Lets keep this discussion in the 19th, 20th and 21st century.

I think Plate Tectonics Theory would fit nicely into this category; perhaps tarred with the same brush as Wegener, Holmes’ idea of a “conveyor belt” type of thermal convection action in the mantle of the earth causing continental shift over time was ignored at best, dismissed at worst, until the 1960s.


what a minute. With Bush & Co. controlling science policy…

I remember that my old Doc Savage books derided chiropractic.

For a long time, many health plans I administered did not cover it either.

The angiogenesis model of cancer. This is the idea that cancer will hijack your bodies ability to produce new blood vessels and thus will recruit its own blood supply. Without the ability to do this, the cancer cannot grow beyond a certain size. The ability to grow new blood vessels is usually not terribly important in the adult human body.

Furthermore, tumors often display the ability to suppress their own metastases, which can lead to the vexing behavior of metastases blooming into larger tumors once the primary tumor is removed.

One guy, Dr. Judah Folkman, noticed this early in his career and has spent decades searching for substances which block angiogenesis. Early in his research, almost nobody would even give him the time of day. He had seen something and made the connections decades before anybody else would have otherwise. His scientific papers would be submitted to journals only to be returned with the damning phrase “Your Research Does Not Support Your Findings”.

His radical hypotheses, that tumors need blood vessels to grow, that tumors will not grow without these vessels, that they recruit their own supply, and that they often secrete proteins or substances that prevent the growth of vessels to other tumors, were quite radical at the time. The prevailing direction in cancer research was overwhelmingly to find new chemotherapy drugs–that is, drugs which are toxic to cells, but more toxic to dividing cells such as the rapidly dividing cells found in malignant tumors.

Ironically, Folkman found support among the industrial sector. Mosanto and other companies supported his research when nobody else would. In fact, Folkman was a central figure in one of the first Industry-Education research partnerships at Harvard.

Folkman focused his efforts on finding the angiogenesis blocking effect often exhibited by tumors. He would eventually aid in discovering two of these (and possibly more), Angiostatin and Endostatin. These substances were successfully administered to mice who had been implanted with human cancer cells which had been allowed to grow into tumors. Using only these drugs, the cancer stopped growing and eventually disappeared entirely.

The first generation of angiogenesis blockers is just now coming available. After Folkman’s efforts, angiogenesis research became a booming field. All of this was expedited by Judah Folkman’s determination, and his solid scientific understanding. This is not a case where he had some fuzzy idea and little to back it up. Dr. Folkman saw that this was occurring, investigated it rigorously, and presented his results. It just happened that the results were so counter to the current directions of research that to somebody who had not taken the investigative approach Folkman did might not understand his reasoning.

Folkman endured criticism, rudeness and outright hostility but persisted and would eventually have his research receive recognition. This is all well and good, if you are actually right. Unfortunately, many people claiming radical findings as Folkman did either are on shaky scientific ground.

Well, proponents of the germ theory of disease were ridiculed I don’t know if that really the same as being considered a pseudo-science or not, though.

Hell, in many cases I deride chiropractic. This is FAR from a proven general therapy, except for some temporary relief for some common back conditions. If a person looks at outrageous claims made by many chiropractors, its easy to see reasons to be dubious.

But don’t take my word for it. Quackwatch.org is an excellent resource.

Better yet, try Chirobase.

If I were a health plan, I would sure cover it. If it causes people to not go to the expensive doctor for otherwise minor or short-term problems, that saves me money whether it is actually effective or not. It’s a purely economic decision in that case.

Chiropractic for a very limited subset of back problems, sure. But not as a general health care solution that I have seen so many Chiropractors advertise of late.

That would be because there are aspects of chiropractic that ARE pseudoscience. Would those plans cover visits to a chiropractor for anything besides acute lower back pain, especially to treat an infectious disease by correcting “spinal subluxations disrupting the flow of innate intelligence?”

Chiropractic students can entertain you the whole evening if you don’t laugh and keep the beer flowing.

Barry Marshall’s idea of bacterial infection causing stomach ulcers was dismissed for several years before finally being accepted by the medical community.

First thing I thought of – some Doper who was a maintenance worker at a chiropractic office, who posted about an incident in which he warned one of these fellows not to get too close, because he had a wicked flu. I still think of the quack’s response everytime chiropractics comes up: I have this little movie that runs in my head of the guy drawing himself up and indignantly declaring “We don’t subscribe to the germ theory of disease here.”

Bwahahaha. Like I’d trust these people with my spine. Right.

I think it is important to make the distinction between emergent theories and pseudoscience. The former are hypthesis or tenative theories which lack a substantial body of evidence that has been validated and accepted by the science community (or those members in field) needed to overturn an existing paradigm. Germ theory, natural selection, quantum mechanics, and so forth were all, in earlier days, embryonic theories whose proponents had to battle scepticism and present predictions that could be falsified before becoming accepted.

Pseudoscience, however, are “theories” that make claims that can’t be objectively falsified. The most common example of this is astrology; since the “science” of astrology doesn’t make any standard claims (ask any five astrologers and you are likely to get eight different predictions about the future) and the claims that are made are vague enough to fit any sitauation, they are unfalsifiable.

Other fields are more ambiguous; the Aquatic Ape Hypothesis, for instance, gives every appearance of being a valid (if highly speculative) scientific claim. However, delving into the specifics of the claims, one can see that they are often contradictory, post-hoc, and ephemeral, when they’re not actually based upon incorrect supposition, such as the alledged unique existance of subcutaneous fat in H. sapiens. For instance, the now-discarded claim of holes in the fossil record is replaced by the rationalization that the short timespan of existing holes argues in favor of rapid bursts of radical evolution. :rolleyes:

Note that just because a theory is insufficiently supported or validated doesn’t necessarily make it wrong. For decades Darwin’s theory of “Descent with Modification” (what we now call Natural Selection) lacked a causitive mechanism; Lamarckism (transmissability of inhereted characteristics) made far more sense from a rationalist point of view…until Gregor Mendel’s experiements with inheritance, which ultimately lead to the discovery of genetics and DNA, gave Natural Selection the tools it needed to be a complete theory rather than an unsupported model.

The general distinction one can make between genuine science and pseudoscience is that the former states hypotheses that can be tested and falsified, never insisting on having the “ultimate truth” but rather always continuously spiraling in on a more comprehensive and complex understanding of the principles involved, whereas the latter is based upon one or more identifiable fallacies and makes unsupported, untestable or irreproducable, and speculative claims that intended to be accepted on the word of authority or belief.

Note that (at least, for the most extreme advocates of these fields) this places theories of extraterrestrial life and superstring theory in the domain of pseudoscience; claims that can’t be (currently or in the foreseeable future) falsified or reproduced. It doesn’t make them wrong, just unworthy of being accepted as a theory rather than errant (if highly reasoned and debated) speculation.


Another excellent post Stranger. I was reading down the page and trying to formulate a similar response in my head until I read yours and saw I was thoroughly superseded.

excellent post.

A recent article in Skeptical Inquirer pointed out that the time between the first presentation of this hypothesis and its general acceptance by the medical community – about ten or fifteen years, IIRC – was taken up by experiments that validated it. In other words, it was science working as usual.

Although at first it was doubted by doctors who had long believed that ulcers were caused by stress, that doubt did not obstruct the process of testing the theory. Marshall has apparently made some publicity hay out of portraying himself as the underdog, but despite this, it would be incorrect to characterize his hypothesis as pseudoscience. Nor was the idea suppressed by misguided opponents.

People pushing pseudoscientific ideas and out and out scams like to give themselves credibility by suggesting that there are lots of “truths” that were once derided as “nonsense.” But there are far fewer such cases than they would have you believe. As mentioned above, plate tectonics is perhaps one of the “best” examples, because of the unusually long period that elapsed before a plausible mechanism for how it could work was discovered.

(Oh, and excellent post, Stranger.)

At one time (and this extended into the 19th century), many, if not most, scientists refused to believe that rocks could fall from the skies.

Well, some emergent theories are more ridiculed than others. The idea that fermentation was caused by microorganisms was heartily ridiculed until Pasteur proved it.

“All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident.” - The Schopster

I think that lasted well into the 20th century.

Spontaneous Human Combustion is now probably explained and accepted by many scientists as the Wick effect . Sertainly after seeing the telivised results of the wick effect using a pig carcas on QED UK tv programme I am pretty well convinced.

Couldn’t it be argued that both hypnotism and TMS grew out of the work of Anton Mesmer? Both are generally considered avenues of conventional medical research today, though both continue to attract a sizeable pseudoscientific following as well.

Of course, Mesmerism wasn’t merely considered pseudoscience, it was pseudoscience, so perhaps that doesn’t count as far as the OP is concerned.

Acupuncture/acupressure. Like chiropractic, it has a whole lot o’ hoopla attached to it, but certain applications do work. There is a commonly available anti-nausea wristband that puts pressure on a spot on the wrist and is very effective for many people with morning sickness or motion sickness.