Seeing a hummingbird on the way back from the library, I pointed it out too late for D to see. And carefully mentioned that hummingbirds hum with their wings. Only possibly because they don't know the words. And began a rather protracted rant on people trying to bust a commonly held belief with dubious rebuttal. I had a woman cutting my hair who objected when I told her my hair tended to be greasy.
"It's not the hair that's greasy, it's the scalp!" She corrected me with absolute certainty.
Well, actually, I know that it's the oil from my scalp that gets onto my hair, but I didn't SAY my hair produced the oil. Any more than if there is grease on a table that I think it came from the table, instead of the fries. After all these years, this still sticks in my mind.
I had one of those enthusiastic science teachers in grade 8, never looked at the book, lots of stories and animation. Well, I'd gone on a tour of a nuclear power plant with Aunt Evelyn and Uncle Ernie on a trip through Ontario, and learned about heavy water, and the isotope deuterium. And what it is used for. So when I got back to class, hoping for more information, she confidently told me that heavy water was water with a lot of minerals in it. Disillusioned, I lost a lot of my trust in showy teaching. My high school science teacher gave me the right answer the next year, after double checking his answer - to my admiration. I was one of the few who didn't defend Mrs. Z's data when it conflicted with his.
My older brother, a science geek in his last year in high school, refuted my statement that the water was getting hotter as it boiled longer. "Water gets to the boiling point, then it turns to steam, it can't get hotter than that." Perhaps only nine, I remained deeply suspicious. It took a long time for me to figure out that I was right - sort of - after all. Water can certainly superheat, water under pressure gets hotter, and it does not instantly turn to steam in all cases when it hits the magical 100C. There can be complicating factors.
Many commonly held beliefs are not strictly correct, but simply refuting them often leads to the error of simplification to the point of inaccuracy. Got any others?
8 comments:
My grandmother told me the following more than once: a doctor informed her that no-one had ever fallen and broken their hip - they fall because their hip breaks or is about to.
Now I'm dubious about this, and I believe it was many years ago that she received this information, but I remember it all the same.
V = IR is a common physics relationshop between volts, current and resistance. As stated it holds true under ideal conditions, change the temperature of the resistor or change the length of the circuit and this relationship now becomes close to true but not exact.
The V=IR relationship I learned in the latter years of high school, the more detailed information I learned in a semiconductor physics course in university.
trousers,
That CAN happen, in people with osteoporosis, but it's not an absolute at all.
Phil,
Funny how often ideal doesn't happen, don't it?
I would share the same conclusion as you, zhoen, re hips and breakages. It sounds only sensible.
I had issues with low blood sugar, and a physician told me to eat a diet high in fiber. His nurse gave me a pamphlet outlining a high-fiber diet and its happy effects on regularity. Common wisdom at the time said that a diet high in protein was the way moderate blood sugar. I was disgusted with the guy, and never went back.
I now know that studies suggest a diet high in vegetables and fruits and low in fat is preventative for Type II diabetes, and that fiber does help moderate blood sugar to some degree.
I still don't know if the guy was a kook or just a bit ahead of his time.
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The greasy hair bit made me blink and laugh.
Moira,
My general opinion of nutritionists is that they throw everything out there with utter confidence, so that when they change no one can follow enough to notice. The research is just not there for the amount of certitude they evince.
Any research involving food and nutrition is immediately suspect, because designing good experiments is so difficult. Trying to control everything that your subjects eat is both expensive and futile, while trusting them to be honest (especially if they're being paid to participate) is a great leap into the dark.
Not to mention the fact that whenever a nutrition experiment contradicts the way we think things are, the media immediately trumpet it, regardless of any glaring flaws it may have.
explaining perceived color
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