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Why do we still teach people to calculate?

freakonomics.com

61–70 of 89 posts

Re: Why do we still teach people to calculate?

#61

"because you live in a country where the primary purpose for you as a citizen is to go into debt, so you better know how to, at the very least, do financial planning"

Arguably, being able to do financial planing will keep you out of debt. At the same time the number of people who understand compound interest is shockingly low - a great boon for credit issuers hoping to exploit you.

It would be fanstastic if they taught it in school. They don't, though, which is all kinds of questionable.

Re: Why do we still teach people to calculate?

#62
post #2

Because you need to be able to run numbers in your head for a lot of practical tasks, and inability to do napkin math can cost you very dearly

And calculators get broken very quickly on construction sites. And you must be capable of adding and subtracting and finding the LCD and GCD of fractions to read a tape measure in US customary units.

If durability is the chief constraint, and tape measures are adequately durable and already on-hand for the work being performed, then:

The tape measure itself can be used to perform basic arithmetic, and will even return results in Freedom Fractions if that's how it is labeled.

Re: Why do we still teach people to calculate?

#63
post #14

Yes we should start my six year old with group theory. When we go to the farmer's market I can ask him under what transformations is an apple invariant, and then pay for it by having him solve a Rubiks cube.

A pile of apples (or a stack of one dollar bills) would make a pretty natural introduction to the Peano axioms, and from there the basic mathematical operations.

- A pile without apples is a pile of apples. We call it the empty pile.

- The successor function is to add an apple to the pile. Apply the successor function to the pile of apples and you still have a pile of apples.

- A pile of apples is as large as itself

- If the left pile has as many apples as the right pile, then the right pile also has as many apples as the left pile

- If you have two piles of apples you can add them by checking if the second pile is empty. If it is empty you are done and the result is in the first pile. If not take an apple from the second pile and add it to the first pile. Then check again and repeat

And then you can teach him about the bijection between money and apples. After a little more set theory you can start constructing two piles of apples, one representing what you have one what you have to give away ...

The possibilities are endless.

Re: Why do we still teach people to calculate?

#64
post #28

Earlier quoted context omitted.

What is going on with your tape measures? Confused european over here.

Customary units are given in fractions of an inch. Eg half, quarter, eighth, sixteenth etc. So you’re dealing with simple fractions. That is why I buy tape measures that also have metric scale - to sidestep all that bullshit entirely when adding, multiplying, dividing or subtracting, yet be able to measure distances in inches too

I keep a fractional-inch tape measure in the toolbox in my work truck because that's what everyone else (in the US) has, and I need to be able to work with others. I also have to carry around two sets of wrenches, two sets of sockets, two sets of Allen keys, and it's all quite frankly absolute bullshit. But that's the world I get to participate in.

At home in my own geeky little workshop, where I don't need to satisfy anyone else's proclivities, everything is exhaustively and exclusively metric-only. My tape measures are metric, my hand tools are metric, my drills are metric, and my fasteners are metric. Working with Freedom Fractions is absolutely forbidden in my workshop (as are all screws with Phillips, JIS, Pozidrive, or Reed-Prince heads, but that's a different rant).

And, I must say: It's better this way.

Re: Why do we still teach people to calculate?

#65

Earlier quoted context omitted.

If you run every basic calculation through a calculator, you'll make every task take 3x time it requires today, in best case. I have seen people eyeball measurements and taking notes, and bringing in perfectly manufactured goods (blinds, cupboards, etc.) in return. Esp, in construction, nothing is precise, so being able to eyeball correctly after a quick measurement with a tape and doing some basic math on the number…

I just left a comment on a different thread about detached from reality a lot of tech workers are, and then here I find a guy being like "but rugged calculators are a thing, why do you need to do math in your head?" Tell me you have never built a thing[1] in your entire life that was more complex than an IKEA bookshelf without telling me that challenge: I do hobby projects all the time and I couldn't even tell you ho…

I never said you don't need to do math in your head. I said that the argument "calculators are fragile, so you have to do math in your head" doesn't hold water. You're arguing something different, which I tend to agree with.

Re: Why do we still teach people to calculate?

#66

Earlier quoted context omitted.

And calculators get broken very quickly on construction sites. And you must be capable of adding and subtracting and finding the LCD and GCD of fractions to read a tape measure in US customary units.

> and finding the LCD and GCD of fractions to read a tape measure in US customary units. Well, that's what tolerances are for. I don't need a perfectly accurate answer. Just one that's within 1/32" or more likely 1/4" to 1/8".

I don't see what tolerances have to do with it? You still have to do math if you have to site a member between two other members regardless of the tolerance. For example, to frame an 8 foot wall you have to cut your studs down to accommodate the top plate and bottom plate and the trim plate above the top plate. Similarly with windows, doors, and headers. Whether you have a 1/16 tolerance or a 1/8 tolerance it doesn't matter. The only time I've had to deal with tolerances when framing is in making sure the drywall doesn't wave anything around by firring out or planing down each stud to put the wall into tolerance.

Re: Why do we still teach people to calculate?

#67
post #28

Earlier quoted context omitted.

What is going on with your tape measures? Confused european over here.

Customary units are given in fractions of an inch. Eg half, quarter, eighth, sixteenth etc. So you’re dealing with simple fractions. That is why I buy tape measures that also have metric scale - to sidestep all that bullshit entirely when adding, multiplying, dividing or subtracting, yet be able to measure distances in inches too

The decimal point was discovered very late in American mathematics.

Re: Why do we still teach people to calculate?

#68

Earlier quoted context omitted.

> Mathematicians are very much in davis/hersh "what is mathematics anyway" This reminds me of getting my CS degree in the early 2000s, then slowly realizing that my comp-sci program had taught me lots of interesting things about how computers and programs work, and essentially nothing about how to write code for a living. Also reminds me of playing Dominion (the card game) with another student, me saying "Okay, I've…

I got my degree in the mid 90's and let me tell you - high school guidance counsellors in the 1980's had no clue at all what computer science was. I arrived at university expecting to be writing a lot of programs and was soon struggling with a heavy load of mathematics and proofs. Our introduction to computer programming professor made it clear that that class was the only one where we would be taught to program. Com…

> high school guidance counsellors in the 1980's had no clue at all what computer science was.

My problem was that the fucking college counselors didn't know either.

When I signed up, I told the lady I wanted to be a computer programmer, and she said "You'll want computer science, then," and that wasn't true. The CS program was only interested in teaching me how to be a CS professor. A few years in I was scouring the course lists for classes on graphics, web, anything with a GUI even, and there was nothing. It was 100% command line C++, and they didn't even bother teaching us about IDEs and debuggers. Just Telnet, vi, g++.

It was like taking a pure math degree to become an architect.

Re: Why do we still teach people to calculate?

#69
post #51

Earlier quoted context omitted.

> Mathematicians are very much in davis/hersh "what is mathematics anyway" This reminds me of getting my CS degree in the early 2000s, then slowly realizing that my comp-sci program had taught me lots of interesting things about how computers and programs work, and essentially nothing about how to write code for a living. Also reminds me of playing Dominion (the card game) with another student, me saying "Okay, I've…

At the end of the day, writing code is not difficult. Understanding what it's actually doing is the hard part. Moreover, understanding how to write code that reasons about code (and higher) is when you start to need computer science, or really just axiomatic systems (math).

> At the end of the day, writing code is not difficult. Understanding what it's actually doing is the hard part.

That sounds nice in the abstract, but in practice it's slow going trying to do web dev when your experience is nothing but command line C++.

Re: Why do we still teach people to calculate?

#70
post #14

Yes we should start my six year old with group theory. When we go to the farmer's market I can ask him under what transformations is an apple invariant, and then pay for it by having him solve a Rubiks cube.

You joke, but it's become a thing for kids to do Rubik's cube. I think it's great for algorithmic thinking. My kid has a whole bunch of classmates who spend their time cubing, going from one algo to a more advanced one, discussing with their friends.

When I took Abstract Algebra 1, I had to sit in the front row because I was too cheap to buy glasses.

I learned about commutators from a guy on the front row who was really good at Rubik's cubes. Concrete examples relatable to your hobbies are great.

I also tried to pay for my lunch by commutating, but the lunch lady wouldn't have it.

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