This is a wrong question. There are numerous aspects of living beings that could have been different without necessarily having an effect on survivability. Many different proteins could have carried oxygen, some probably better than haemoglobin, still specifically haemoglobin carries oxygen in many animals.

Similarly, "such a thing" is just one of the cases which helped animals survive. Something else could also have helped us survive and thrive, but the "such a thing" happened, and there need not be a reason why among all these things, just the "such a thing" evolved and not others.

Wrong question again. Having calcium phosphate in bones doesn't drive human behaviour either, still people have have calcium phosphate in bones. Having 2 (and not 3, not 4) hands doesn't drive human behaviour, still most humans perceive themselves to have 2 hands.

Agreed that lack of proper competition is the reason for high tariff , I would go so far as to say the only reason other than low population density in the US.

As for metered or unmetered - that is because of a general expectation of stupidity in customers, high cost of customer service, and the impossibility of explaining technicalities in advertisements. It has nothing to do with getting people to use more internet - as most service providers benefit from people using less and paying more. They don't even hide it - the hints of their being an undisclosed upper limit do more to stop technologically illiterate customers from using more, than an unmetered connection does to encourage them.

I call it stupidity, and not merely uninitiated - ness, because electricity meters are similar, but people were not expected to be so stupid back then. Admittedly connection costs vs per unit costs are higher in electricity than internet, the expectation that a layman cannot be expected to know what a gigabyte means, is also a large part of it.

Wrong. When people pay more for using more bandwidth, it encourages investment in infrastructure.

If heavy users and light users pay alike, where would the return on investment on infrastructure come ? Especially with geographical monopolies?

Agreed with other statements, but a perfect "smart gun" would be cool, and more useful than non-smart guns.

Currently one can train for using guns. One of the training subjects is "gun retention" - exactly the topic being discussed. It might be rare for one's gun to be used against oneself, but that is because gun holders take extreme care so that it doesn't happen. Not having to take so extreme a care when already stressed can only help the gun holder.

Another point - gun is a distance weapon. Could be useless when distance between combatants is less than 2 feet. But at times the aggression starts when the attacker is at 2 feet distance, maybe even less. So either the self-defender starts shooting everyone within 30 feet of his/her own body, whether or or not they are aggressive. OR they need to be extremely well trained in close range combat, without using the gun because gun could be useless at low distances. Importantly - at that point, the self-defender would have to weigh the option of trying to use guns - if successful the attacker can be killed / wounded / scared / fended off. But at such close ranges, attacker being a professional, can take the gun. So the self-defendant might not even try to use the gun, which means a wasted gun.

Smart guns are more useful. If combat unfortunately becomes a close range one, the gun holder can still try to use the gun. With non-smart gun, there is a big risk even in trying.

In a couple of minutes, with a caliper, only a very rough estimate of body fat can be acquired - exactly the problem you have with BMI. It doesn't measure body composition, but body surface composition. To eliminate the effects of retained water and skin defects, significant training is required.

But health is too important to be NOT defined in simple ways. Everyone will not study the human body for 10 years. Simple ways to keep healthy, and detect if you could be going wrong are essential. Human body being complex, simple ways don't turn out to be perfect. But I haven't seen a better substitute for BMI.

Duh. There is one degree of freedom - because height does not make one obese/overweight/underweight. BMI is not for measuring body's density - one would use body weight / body volume if that were the purpose, but it is NOT.

And the metric you propose is just not for females. A metric doing 90-95% (your numbers) correct predictions for complex systems like human bodies is doing great - and definitely does not deserve to be replaced by other metrics which pretend meat-balls with low testesterone don't even exist.

In your response, you said "People keep arguing that London's black cabs are better than Uber and therefore Uber should not be allowed to compete with them". Emphasis mine. The poster to which you replied did not argue this at all. He just said drivers of black cabs have been shown to be superior, and can't conceivably be "peer" to ones with lower barriers to entry. So your strawman has 2 variances with that poster :
1. No "therefore" or equivalent in that post
2. He didn't say Uber should not be allowed to compete - just that they are not peers. So Uber drivers paying extra tax might suffice. Or some extra certifications.

No. This post , the medcine doctor example, is similar, just that mine was more in your language - in the sense that some things are better than others and people choose between them. You narrow mindedly reduced choice to taxis rather than whole cities.

The post that I link to above, while essentially being similar argument, didn't use "your" language - but went into how choices have other impacts. The choice with side-effects again IS choice but at a higher level than strictly the object being chosen.

Random request? You came up with random people, with their BMI values, and YOU don't think they are "overweight", without defining "overweight". If you can't go into those people's future from the time the photograph was clicked, and find their health problems, your opinion on their being overweight is meaningless.

Which doesn't really show it is preferable. It doesn't answer the women question. Secondly, a large majority of men develop lots of fat only near their abdomen. While waist to height ratio does correctly predict higher CVD incidence for such people, the pattern of diffuse fat deposition all through the body causes higher joint strain. Waist to height ration does nothing to predict that. This diffuse fat deposition pattern while being more popular in women, is not limited to women.

If you narrow down the purpose of a metric to CVD prediction, that too correctly only in males, waist to height ration could be said to be better.

Funny, you don't consider the ~50% women important but 5-10% "incorrect" predictions makes BMI a "lie" ?

Waist to height ratio doesn't work well on females because with low testerone levels, fat deposition isn't primarily around the waist. False positives are because it catches the health risks due to hormone imbalance in women. A large paunch is anyway a health risks in males, so this metric doesn't bring much to the table.

BTW you haven't posted health risks in future for the individuals by whose photographs you declared them non-overweight.

Actually exercise reduces food cravings. See this and this. I admit these don't sound like the last word, scientifically, but I have other arguments :

1. Personal experience - being an irregular exerciser, I know both states of mind. The exerciser me yields a lot less to temptations.

2. Comfort food : Lots of people eat because they are depressed. Exercise reduces depression.

3. That's a lot of stairs : The one who exercises knows that a LOT of exercise is required to burn a little extra food. He also knows the effort / pain/ willpower required to exercise that much. The one who doesn't exercise, doesn't know at least one of these. Since it is a lot of stairs to burn the extra bread, the exerciser is more likely to choose to not eat the extra bread.

From looks, that too clothed? How is your opinion any useful?

For a metric to be successful, it should be fit for a purpose. The purpose of BMI is NOT to tell whether a person looks overweight to Alomex when appropriately camouflaged in clothes.

The purpose of BMI to be an easy to compute formula for easy to obtain raw metrics to determine chances of disease. It is a difficult problem to solve. If the only objection to BMI is that overweight people according to BMI "look" non-overweight to you, that is a great metric.

Do you have an alternative ? Equally easy to calculate on equally easy to obtain raw metrics with better chance of predicting lifestyle disease than BMI? You could win a Nobel. Though I guess like all nit-picking-non-Nobel-laureates, you just don't understand the purpose of things you are picking nits in.

It is not that the black cabs are better than Uber cabs. It is that the London (+ suburbs) which can only have black cabs is expected to be better than the London (+ suburbs) which can have non-black cabs. Expected by the people of London, and I can see why they expect this.

May not be true, but the decision should be theirs.

0 and 1

That is all the numbers you will ever need.