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Comment by TeMPOraL | Hacker News Reader

Learning the truth about many of those misconceptions even before discovering the whole list is what ultimately broke my trust in mainstream opinion. The whole time since I left high school has been a period of systematic unlearning of all the bullshit I've been taught - by teachers, friends, families and talking heads. Just how the hell is an adult supposed to live if every other day they discover another thing they thought is obvious is actually wrong? This is one of those things that really pisses me off about reality.

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I've had to unlearn and relearn chemistry like 7 times now (since quantum chemistry finally makes accurate quantitative predictions, I'll trust it for now...)

I know you can't teach third graders quantum mechanics, but I wish they at least wouldn't have taught me wrong stuff that became ingrained into my mind at an early age.

Almost 20 years later, I distinctly remember my high school physics teacher standing at the front of the class on the first day and saying "Remember this: everything you will learn from me this year is wrong."

Buck up! I think of it as, zeroing in on truth. Historically we had approximations and good guesses. Now we're in an unprecedented period of discovery and science. Of course we have a lot to unlearn!

That's definitely a good way of looking at it, but still, most of those misconceptions aren't lack of knowledge; it's people presenting bullshit to other people as facts of nature. It's not that we had to discover how, say, microwave oven works - we obviously knew that before the first one ever hit the market! Someone somewhere just invented an explanation and it spread, and most people don't bother to even think twice if it makes sense.

My favorite wrong fact was the simple model of friction we were taught - that force was proportional to surface area and weight. In middle school we were given force gauges and wood blocks. Pull them stacked or linked and graph the force vs weight X area. I got a weird curve. Looking around, I saw everybody else fudging their data to make a straight line. Confusing.

Decades later I heard on the radio "The traditional model of friction has been proven incorrect for many materials" and I thought, I knew that in middle school.

I think you may have misunderstood something here. The high school static fiction model is:

  frictional force = normal force X coefficient of friction

i.e. frictional force is independent of surface area according to this model.

What are the units of that coefficient? Per square? And are we talking force or pressure. Hm.

The experiment used blocks with hook-and-eye screws. You dragged them across the surface linked in a chain, then again stacked, in twos and threes. The result came out nothing like a linear relationship.

The coefficient has no unity. It's N/N. And we are talking about force, not pressure.

By an ideal linear friction, you should have measured the same force on all experiments. But reality is way more complex, and sometimes the ideal model won't give you even a first order approximation.

Your teacher shouldn't have used wood blocks (unless he wanted to make a point), metal ones would give better results.

I'm sorry you've got totally the wrong end of the concept here.

Check out https://en.wikipedia.org/wiki/Friction#Dry_friction

You might enjoy "The Structure of Scientific Revolutions". It argues convincing against the idea that we have not been zeroing in on truth. Our understanding is better then it used to be, but it's not because we're been steadily progressing. It's because we occasionally throw everything out and start over through a "paradigm shift". This book coined that phrase.

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