[quote=CRGreathouse;175284]So, ballpark -- worldwide energy expenditure would be reduced by about 1% if every human being cut the energy equivalent of their diet in half, maybe 2% if they cut it to 10%. Or, alternately, if all humans grew brains five times their current size, this would increase energy expenditures by about 2% ([I]ceteris paribus[/I]).*

To make a real dent in energy use we'll have to change heating, cooling, transportation, chemical production, metalworking, and other energy-hungry sectors.

* Implicit ballpark assumption: the brain consumes a quarter of the body's energy. Modify to suit.[/quote]

Either that or the current energy production could be used to keep 300 billion [I]homo pentasapiens[/I] with average IQs of 165 running.

Who needs heating, cooling, housing and transportation if humans can breed/grow symbiotic exoskeletons capable of photosynthesis and omni-communication?

[QUOTE=__HRB__;175317]Either that or the current energy production could be used to keep 300 billion [I]homo pentasapiens[/I] with average IQs of 165 running.[/QUOTE]

You think 165 is all you'd get? I'd think that, under the current definition of IQ, their intelligence would be literally undefined (or infinite, in the sense of being greater than any finite IQ). (This is not a claim that their intelligence would be unlimited or infinite.)

[quote=CRGreathouse;175349]You think 165 is all you'd get? I'd think that, under the current definition of IQ, their intelligence would be literally undefined (or infinite, in the sense of being greater than any finite IQ). (This is not a claim that their intelligence would be unlimited or infinite.)[/quote]

I picked the number, because it would label today's average human a 'moderate mental retard' suitable for 'very simple tasks under close supervision'.

But you are right, 165 is probably too small. According to

[URL]http://homepage.mac.com/wis/Personal/lectures/primate-adaptation/10PrimateBrains.pdf[/URL]

Chimps [I](Pan troglodytes) [/I]have 3/8ths of the Encephalisation Quotient (EQ) of humans, and according to

[URL]http://www.paulcooijmans.com/intelligence/iq_ranges.html[/URL]

Chimps have average IQs of 35-50, so we could guess that IQ scales as EQ^a (with 0.7<a<1.0), and if [I]homo futurus[/I] has 5x bigger brains but today's overall body mass, they'd have average IQs between 300 and 500 (read: have problem solving abilities corresponding to someone with an IQ of that magnitude).

Half the world have above average IQ's.
And most people have more than the average number of legs.

[quote=Uncwilly;175364]Half the world have above average IQ's.[/quote]

Did you figure this out by yourself, or did your supervisor tell you after you completed a very simple task?

IQs cannot be negative, so the distribution is slightly skewed towards zero (i.e. the distribution is ony approximately normal, but actually follows a log-normal, or some F distribution), which means that in fact [U][I]less[/I][/U] than half have above average IQs.

[quote=Uncwilly;175364]And most people have more than the average number of legs.[/quote]

Then I'm sure you also believe that most people have more than the average number of brains, since making such statements is only possible if a person has exactly zero brains.

[QUOTE=Uncwilly]And most people have more than the average number of legs.[/quote]

[QUOTE=__HRB__;175403]making such statements is only possible if a person has exactly zero brains.[/QUOTE]
Uncwilly is right on this one. The average number of legs a person has may be 1.99 or 1.999, but it's less than 2. That's because the number of people who have one or no legs outnumber people who have three or more legs. (Note: The only three-legged person I know exists is this one: [url]http://www.jbjs.org.uk/cgi/reprint/34-B/4/630.pdf[/url] ).

Of course, most people have 2 legs, which is more than the average. Therefore, most people have more than the average number of legs.

[quote=MooooMoo;175417]Uncwilly is right on this one. The average number of legs a person has may be 1.99 or 1.999, but it's less than 2. That's because the number of people who have one or no legs outnumber people who have three or more legs. (Note: The only three-legged person I know exists is this one: [URL]http://www.jbjs.org.uk/cgi/reprint/34-B/4/630.pdf[/URL] ).

Of course, most people have 2 legs, which is more than the average. Therefore, most people have more than the average number of legs.[/quote]

Sigh.

The arithmetic mean is meaningless for discrete data. Anybody with a non-empty set of brains would have realized this. With zero brains, you can also conclude that one degree Fahrenheit is infinitely hotter than zero degrees Fahrenheit because 1/0 is +inf.

Innumeracy is greatly responsible for the unrealistic risk-assessment of global warring ([I]sic[/I]). This is not the result of too little education, but rather that too much education has created delusional morons, who erroneously believe that knowledge qualifies them to think.

[QUOTE=__HRB__;175423]The arithmetic mean is meaningless for discrete data.[/QUOTE]

I consider myself a reasonably intelligent person, but this statement made absolutely no sense to me. Care to explain?

[QUOTE=__HRB__;175403]IQs cannot be negative, so the distribution is slightly skewed towards zero (i.e. the distribution is ony approximately normal, but actually follows a log-normal, or some F distribution), which means that in fact [U][I]less[/I][/U] than half have above average IQs.[/QUOTE]

I don't agree with that at all. IQ is by definition normal.

There's no reason to avoid negative numbers -- it's just that they'd be very rare. You'd expect a 1.3e-11 fraction of people to have a negative IQ, or about 0.1 people on Earth.

[QUOTE=__HRB__;175423]The arithmetic mean is meaningless for discrete data.[/QUOTE]

:huh:

[quote=philmoore;175424]I consider myself a reasonably intelligent person, but this statement made absolutely no sense to me. Care to explain?[/quote]

Can you construct an example where the statement "the average person has 1.999 legs" is meaningful? For example, if you pick a person at random, would you conclude that guessing that the person has 1.999 legs is a good idea?

Since nobody has 1.999 legs, the statistic is meaningless, but e.g. the mode "the most common number of legs a human has is 2" is a meaningful statistic.

Just in case: even rounding doesn't help, because e.g. a statistic like "the average human has one testicle" doesn't mean anything.