> the value of a life didn't feel proportional to the value of a lifetime, though i never really objectively understood why

Probably because no single person loses their entire remaining lifetime due to slower traffic, vs the person who dies in traffic that does.

There’s also something to be said that sitting in traffic is life. At least as much as getting wherever you were going to go faster, likely to just sit there instead.

Sitting in traffic is not real life. Real life is bingeing Netfix series!

Why not both?

The self-driving dream.

Ashamed to say, but this made me bust out laughing with concerned looks from co-workers. Thank you.

If you have a question or think they're wrong about something, please take ten seconds to explain it. This comment doesn't help anyone.

> I worked out that it would cost an extra 50 lifetimes a year sitting in traffic.

Sitting in traffic is not the equivalent of being dead, so it's not as bad. The other side of the argument is that the people sitting in traffic are missing out on their peak years, while the reduced lifespan from a traffic death removes the last years, which at best are less enjoyable.

> While the reduced lifespan from a traffic death removes the last years, which at best are less enjoyable.

I can't tell if that's a joke or not.

It's not a joke. Losing 30 minutes of your life when you're 25 costs you 30 minutes when you're healthy and full of energy. The average person experiences all kinds of problems after 75 (hips are bad, diabetes, effects of stroke, and so on). Conditional on having to choose when to give up part of your life, which is the tradeoff I was responding to, virtually everyone would choose after 75 rather than a younger age.

To the contrary - In many countries, average happiness is higher when you are older, despite physical challenges. The lowest happiness is typically in the 30s and 40s.

If you want to approach it from a happiness utilitarian perspective, a year at 60 or 70 is usually worth more than a year at the lifetime average happiness.

Various sources show something like this: https://www.brookings.edu/wp-content/uploads/2020/12/201207_...

Random traffic accidents don't target sick people.

> Sitting in traffic is not the equivalent of being dead, so it's not as bad.

I would argue that it is considerably worse, since people sitting in traffic generally have to be conscious during the experience, which is not the case for being dead.

Surely if you're "sitting in traffic" it doesn't matter if the speed limit is 30, 20, or 5 mph?

When I worked on a product with 10s of millions of users we could say things like "Yay! this 0.2 second improvement in page load will save 5 persons lives this month".

(but we did it as a joke)

Major "Broomshakalaka" vibes

How would it cost extra lifetimes to people sitting in traffic? If there's sufficient traffic to slow traffic meaningfully from 30mph, a 20mph limit isn't going to make a difference?

reminds me of the ted talk where the speaker said that helmet laws might be costing lives. The idea was that more people would be saved by the opportunity to exercise than were saved by the helmets.

I think this one?

https://www.youtube.com/watch?v=07o-TASvIxY

I think Australia saw a drop-off in cycling after they made helmets mandatory.

There was also some evidence that drivers give cyclists more room if they see they aren't wearing a helmet.

Personally I'm going to buy some pink lycra as I've noticed my wife gets far less aggravation from drivers than I do when we are out cycling.

Or maybe a tandem? ;0)

The collective time everyone sits in traffic is not the same as someone actually dying.

Right: unlike dying, if someone sits in traffic more, they're able to change their situation and seek alternatives. It's not like increasing traffic in the short term is something reasonable to extrapolate to all drivers for the rest of their lives. More likely, traffic increases lead to either (or both) of infrastructure changes or lifestyle changes.

Also the conversation assumes people are actually sitting in traffic for ages Are the welsj streets so clogged? I recall an article stating that the average increase in journey length was a few minutes.

These kind of talks always came up in philosophy class and I always made the same point - there isn't saving a life, we are all dying/will die, singularity permitting. Dying just means dying sooner, lifetime QoL should be the only metric for us mortals.

It's just the calculus suffers from the same existential problem as abortion morality - how do you weight a lived life vs non-existence?

QALYs are generally how this done, and don't need to be limited to medicine: https://www.sciencedirect.com/topics/medicine-and-dentistry/...

They won't help you with non-existence though.

Yeah, the calculus needs to be more complex:

* not clear 2 * 50% QALY == 1 * 100% QALY

* maybe factor in "non-existence" with expected life expectancy?

* need negative QALY to factor in pain, dissatisfaction

Note that 4 or 5 fewer death probably also translates to 8-10 fewer paraplegics (statistic made up using that fact that the country where I am from has a 2x ratio between death and paraplegics).

But even that does not take into account secondary effects to reducing the speed limit like fewer people traveling, less air population, people having more time to meditate, etc... All in all, it's very hard to estimate the impact of such policy.

Are you 2x as likely to become a paraplegic after a motor vehicle accident at 30mph as you are to die? That doesn't sound right.

> fewer people traveling

I don't think anyone says to themselves "it's a 20mph zone on the route so I'm not going, if it was 30 I would go." Lower speed limit != fewer travelers.

> less air population

Assuming you meant pollution, the same amount of cars going slower would cause more pollution in a given area, not less.

> people having more time to meditate

I'm sorry what? Most people don't meditate, and how is sitting in the car longer going to give you more time to meditate?

> Lower speed limit != fewer travelers

Longer travel times result in fewer people wanting to travel. Was not expecting this to be controversial.

> The same amount of cars going slower would cause more pollution in a given area

Drag is proportional to the square of the velocity

> Most people don't meditate, and how is sitting in the car longer going to give you more time to meditate?

Meditate is perhaps the wrong word.

>Assuming you meant pollution, the same amount of cars going slower would cause more pollution in a given area, not less

In general the slower you drive the lower your mpg (and hence pollution).

I always assumed it was about slowing cars from 35 to 25mph as hardly anybody sticks to the speed limit.

Llywodraeth Cymru (Welsh Government) claims that a public health study suggests its new 20mph limits will see, annually, a 40 per cent reduction in collisions, between six and ten lives saved, and anything from 1,200 to 2,000 people avoiding injury as a result.

Scale that up across the country and you are looking at way more than "4 or 5 lives".