4 ms·

Because being able to do basic order-of-magnitude arithmetic in one's head is a critical thinking tool essential to detecting nonsense claims in real time.

extrn 2y ago
Precisely. It is critically important to develop the correct cognitive abstractions.
ComposedPattern 2y ago
In the schools I'm familiar with, this isn't really a skill that's taught. The emphasis is on carrying out steps correctly on paper. Making a good estimate without showing work would definitely be frowned upon.
- cassianoleal 2y ago
  Taking the steps multiple times (practicing) will make it fast and trustful. Guessing may get you a part of the way if you're very good at it, but repeatability is what really hammers it into you. It also gets you out of trouble when for any reason your guessing instinct is not at full steam (when tired or otherwise incapacitated, anxious, etc) since you can usually relatively quickly rely on the steps you have drilled for.
- wongarsu 2y ago
  In Germany this was part of the physics curriculum. It made sense since order-of-magnitude estimations constantly come up naturally in all fields of physics, whether you are asking "is this plausibly possible", "what kind of instrument do I need for this measurement" (and later "can we even measure this in this setup") or "are the results of my experiment plausible". There's a reason we joke that to the physicist g=10 and pi=3. It's difficult to test this kind of thinking in a written test without turning it into something entirely different, but not everything in school has to be on a test. Typically half of our marks were made up from classroom participation.
  - pklausler 2y ago
    Once you learn how to use a slide rule to estimate a calculation to just one or two significant digits, you no longer need the slide rule.
throwup238 2y ago
It’ll also help you from getting ripped off, whether that’s a cashier mistakenly giving you the wrong change or friends calculating a restaurant split in their favor, or a malicious business trying to screw you over (banks!). Mental arithmetic is vital to mental self defense.
- piker 2y ago
  Interesting how malice is implied in the safest circumstances and mistake in the most hostile in those examples.
nerdponx 2y ago
It's also just useful. If I and my coworkers had to constantly stop to pull out a calculator (or an equivalent app) to compute anything, we'd never get anything done.

extrn 2y ago

Precisely. It is critically important to develop the correct cognitive abstractions.

ComposedPattern 2y ago

In the schools I'm familiar with, this isn't really a skill that's taught. The emphasis is on carrying out steps correctly on paper. Making a good estimate without showing work would definitely be frowned upon.

cassianoleal 2y ago
Taking the steps multiple times (practicing) will make it fast and trustful. Guessing may get you a part of the way if you're very good at it, but repeatability is what really hammers it into you. It also gets you out of trouble when for any reason your guessing instinct is not at full steam (when tired or otherwise incapacitated, anxious, etc) since you can usually relatively quickly rely on the steps you have drilled for.
wongarsu 2y ago
In Germany this was part of the physics curriculum. It made sense since order-of-magnitude estimations constantly come up naturally in all fields of physics, whether you are asking "is this plausibly possible", "what kind of instrument do I need for this measurement" (and later "can we even measure this in this setup") or "are the results of my experiment plausible". There's a reason we joke that to the physicist g=10 and pi=3. It's difficult to test this kind of thinking in a written test without turning it into something entirely different, but not everything in school has to be on a test. Typically half of our marks were made up from classroom participation.
- pklausler 2y ago
  Once you learn how to use a slide rule to estimate a calculation to just one or two significant digits, you no longer need the slide rule.

throwup238 2y ago

It’ll also help you from getting ripped off, whether that’s a cashier mistakenly giving you the wrong change or friends calculating a restaurant split in their favor, or a malicious business trying to screw you over (banks!). Mental arithmetic is vital to mental self defense.

piker 2y ago
Interesting how malice is implied in the safest circumstances and mistake in the most hostile in those examples.

nerdponx 2y ago

It's also just useful. If I and my coworkers had to constantly stop to pull out a calculator (or an equivalent app) to compute anything, we'd never get anything done.