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  • Well, I thought we'd kick off by doing little experiment with you, Brady.

  • I've gotta wait here on Dhe.

  • I want to see how sensitive your hands are.

  • Ass don't mean I want you to lift some weights.

  • This is a workout session on dhe.

  • I want to see if you can tell difference between how heavy different things are.

  • So I think in the tape camera, it's fine.

  • You're fine.

  • You're fine.

  • This is not the most flattering angle day.

  • Which one of these is heavier?

  • That one.

  • Correct.

  • Correct answer.

  • Right.

  • Said that one is a look.

  • Yeah, 120 grands.

  • And in your other hand, you have 100 grams.

  • Okay.

  • Okay.

  • Now I'm gonna make it slightly harder.

  • You could tell the difference between 120 100.

  • Say you can sense 20 grand difference then, is what you're shooting vaguely usable types, eh?

  • Okay.

  • Okay.

  • Um, now have got No, I feel like that's heavier.

  • Incorrect.

  • So that is 200 grounds and 220 and you can't tell the difference.

  • And there is a reason for Okay.

  • Okay, So what was going on?

  • There is something that Ernest Weber discovered in 18 34.

  • When you did exactly this experiment, he noticed that even though you can sense a small change in between two weights when the initial wait is very small, as the initial weight gets bigger, you can no longer detect that change the just noticeable difference that you need changes depending on the size of the weights.

  • Now this lead him.

  • Thio come up with an equation, which is known as Webber's law, that small difference that tiny change in the intensity, if you like.

  • Of the of the feeling, um, depends, it's a ratio really that you're you're sensing on.

  • That ratio is constant, so there you can detect a 20 ground difference.

  • When you got 100 grams your hand, you can't detect it.

  • When you're a 200 times, you need a much bigger difference.

  • That smallest, just noticeable difference before he can detect it is is that although in weights, you know often in that situation where you're testing different ways.

  • Actually, I think that this Webber's law applies to a lot of different situations.

  • So, you know, if you're in a really dark room and someone maybe turns on their iPhone torch and you can see it kind of like lights up the entire room.

  • But when you're in a really bright room, if someone flicked on their torture wouldn't make, you wouldn't notice the difference.

  • And this explains why, as you get older years seem as though they're they're going faster.

  • Time kind of speeds up as you get older, right?

  • Even though a year is the same length, Always the ratio off how long that year is, how long your life has been end up getting smaller and smaller and smaller.

  • So how it feels changes over time.

  • So this here is Webber's law.

  • But what it means is that the way that we experience things in life actually follows a logarithms.

  • So if you think about how something feels, your response to something and then you compare that to the sort of intensity of whatever it is you're feeling, so this could be light could be sound.

  • It could be waits the way that this changes.

  • It takes out of this shape here.

  • It's kind of log rhythmic shape.

  • So what that means is, if you start off down here and you're a very low wait, okay, and then you take a really tiny change in the weight.

  • So this 20 ground change So this is gonna be I I Plus, don't I?

  • The difference how that feels is gonna be quite big.

  • But then if you're over here, So now this one will be sort of 100 grounds down here.

  • And let's say when you're over here, you're up 200 grounds.

  • Maybe y axis do small, even if you take the same change in weight.

  • So I passed out, I Let's make this.

  • I won.

  • And I know that same change in stimulus is gonna feel like almost nothing in your response.

  • So, essentially, what this means is the way that we feel stuff the way that we perceive stuff in life doesn't follow a linear relationship actually follow the log rhythmic relationship, which is what this curve here is.

  • Human is quite interesting because when you come across logarithms first in school, which I think that you know, when you're 16 or 17 I feel really counterintuitive.

  • They feel like they don't really mean what sense.

  • But actually, that's exactly how you perceive the world.

  • The exact parameters on this curve change depending on what you're talking about, So there'll be one curve for light.

  • There'll be another curve for sounds of how quickly it goes up and how quickly it bends over.

  • But the basic mathematical structure of this, which has been shown time and time again, all sorts of different experiments, is that we perceive things local rhythmically.

  • If there is a mount, a change in stimulus that you can just about notice on we know exactly because of this equation, where that is depending on what you're talking about.

  • People who d'oh marketing use this completely to their advantage.

  • So I swear that Cadbury's dairy milk over time has gradually got smaller and smaller and smaller on dhe.

  • No doubt it probably has.

  • But the people who just make these decisions No, this equation no, the way that we perceive things look is low grade nic and know the exact amount that they can shrink their chocolate bar by before you notice that that's what they've done.

  • Don't they have to put the mass the weight on the back, but no one check those or they're also really expensive items.

  • They know that they can creep up the price by a much bigger some before you'll notice that the price has changed, whereas things like things that are really cheap.

  • You know, buying point milk or eggs or whatever.

  • You're gonna be a lot more careful.

  • You can only seek up by a couple of pennies before people start tonight.

  • Also, the reason why I came across this was because I was doing some research into how judges make sentences, haven't decide on sentences, and actually, this stuff becomes really important.

  • It's not just of people try to make a little bit more money or noticing different size waits.

  • Three months in jail is three months in jail.

  • It doesn't matter whether you have been in jail for three months already or if you've been in jail for 30 years already.

  • Three months in jail cost the same amount of most taxpayer you still depriving someone of their freedom the same amount boss, The thing is, is that a six month jail term feels a lot longer than a three month jail term.

  • A 20 year and three months jail term doesn't really feel like that much more than 20 years jail time.

  • So as a result, there's the study, which looks at the sentences that people give out that judges around the world give out.

  • And there were these huge gaps in the timelines that they're available to them.

  • And it's because of this.

  • It's because it doesn't.

  • It just doesn't feel like enough of a difference to give someone a sentence.

  • That's not one of these kind of preferred numbers.

  • So you get lots and lots of fine granular sentences.

  • Download and then you just get a nice big round numbers, like 20 years and 30 years because people think rogue rhythmically thank you for watching that.

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  • If the Earth suddenly stopped spinning, may him would ensue.

  • I think that is perhaps a slight understatement, but let's continue what would happen toe objects on the surface.

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Well, I thought we'd kick off by doing little experiment with you, Brady.

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