1545: "Strengths and Weaknesses"

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1545: "Strengths and Weaknesses"

Postby squall_line » Wed Jul 01, 2015 2:16 pm UTC

Image
Title: "Do you need me to do a quicksort on the whiteboard or produce a generation of offspring or something? It might take me a bit, but I can do it."

I'm trying to decide if this is a Comp Sci graduate gone mad, or another body-snatcher.

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Re: 1545: "Strengths and Weaknesses"

Postby Jackpot777 » Wed Jul 01, 2015 2:59 pm UTC

As someone that decided not to have kids and has had a vasectomy, that puts that "strength" out of play for me.

Whether or not that makes me an asset or a liability to the company in the far future? I guess we'll just have to wait and see.

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Re: 1545: "Strengths and Weaknesses"

Postby Eoink » Wed Jul 01, 2015 2:59 pm UTC

I've always wanted to answer the first question with "Over-modesty".
Randall seems to be looking at his stick figures in odd contexts at the moment,

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Re: 1545: "Strengths and Weaknesses"

Postby Whizbang » Wed Jul 01, 2015 3:03 pm UTC

Those are the two worse and least informative questions that any employer could possibly ask. It seems like the only reason anyone ever asks it is because it has become tradition.

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Re: 1545: "Strengths and Weaknesses"

Postby Eoink » Wed Jul 01, 2015 3:09 pm UTC

Whizbang wrote:Those are the two worse and least informative questions that any employer could possibly ask. It seems like the only reason anyone ever asks it is because it has become tradition.


Or maybe it's a test of the interviewee, if they manage to neither look contemptuous nor shout "What a stupid question!!!", then they've demonstrated iron self control.

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Re: 1545: "Strengths and Weaknesses"

Postby cellocgw » Wed Jul 01, 2015 3:10 pm UTC

Well, I far prefer this to the oft-quoted honesty

Meanwhile, first in with 'greatest weakness" is an oxymoron :oops:
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Re: 1545: "Strengths and Weaknesses"

Postby orthogon » Wed Jul 01, 2015 3:14 pm UTC

I love this take on the stupid "strengths/weaknesses" question. I've mentioned before that I was once asked this, and the interviewer seemed genuinely surprised that everyone was answering "I pay too much attention to detail". If I'd known I wasn't going to get the job, I'd have said "that's because it's the standard answer to that question, which is why people stopped asking it in about 1982". But this alternative, presenting a characteristic that is definitely true of all the candidates, is a refreshing change. Other options are "I need a constant supply of oxygen" or "I regularly expel foul-smelling matter from my anus".
Note: I got a bit ninja'd, but what the heck.
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Re: 1545: "Strengths and Weaknesses"

Postby ajo4949 » Wed Jul 01, 2015 3:22 pm UTC

Jackpot777 wrote:As someone that decided not to have kids and has had a vasectomy, that puts that "strength" out of play for me.

Whether or not that makes me an asset or a liability to the company in the far future? I guess we'll just have to wait and see.


Technically speaking, vasectomies are reversible, so "You never know!" ;)

Alternatively, that day has arrived and you are, in fact, an ancestor to no living human. Although I suppose the day won't definitively arrive until you die. But some day it will...strength!

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Re: 1545: "Strengths and Weaknesses"

Postby keithl » Wed Jul 01, 2015 3:29 pm UTC

Eoink wrote:Randall seems to be looking at his stick figures in odd contexts at the moment,
I presume Randall created and stockpiled most of the recent xkcd strips months ago, so he had time to work on Thing Explainer, or be ready for the distraction of the next book tour, or prepare for the July 14 return of what-if. These strips could be dispensed by a cron script.

Perhaps he is even dead, lying in a pool of congealed blood, resulting from his unwise attempt to build a velociraptor from the blueprint he was preparing for Thing Explainer. How do you say "velociraptor" in upgo?

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Re: 1545: "Strengths and Weaknesses"

Postby Flumble » Wed Jul 01, 2015 3:33 pm UTC

I'm bothered by his strength statement. There may be a non-empty set of descendants that never acquires your DNA while at the same time there's a non-empty set of descendants that can be traced back to you. The only way to be sure, is by making sure there is no offspring from other males (assuming male) or other females (assuming female). This requires at best that they must all be sterilised and at worst, well, anything worse.

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Re: 1545: "Strengths and Weaknesses"

Postby HES » Wed Jul 01, 2015 3:41 pm UTC

keithl wrote:How do you say "velociraptor" in upgo?

Two leg fast kill.
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Re: 1545: "Strengths and Weaknesses"

Postby orthogon » Wed Jul 01, 2015 3:45 pm UTC

Flumble wrote:I'm bothered by his strength statement. There may be a non-empty set of descendants that never acquires your DNA while at the same time there's a non-empty set of descendants that can be traced back to you.

Technically I'm sure that's true, but I can also believe, without doing the maths, that in the limit of infinite generations the probability tends to zero. Complete extinction of your line is one stable outcome, and father/motherhood of all people alive is another stable outcome, whereas anything in between is at best metastable.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1545: "Strengths and Weaknesses"

Postby da Doctah » Wed Jul 01, 2015 3:54 pm UTC

In the event the human race dies out altogether, you'll simultaneously be the ancestor of all living humans and none of them.

(My strength is that I understand that any statement made to describe all members of the empty set is true. My weakness is that nobody else does.)

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Re: 1545: "Strengths and Weaknesses"

Postby chris857 » Wed Jul 01, 2015 3:56 pm UTC

orthogon wrote:
Flumble wrote:I'm bothered by his strength statement. There may be a non-empty set of descendants that never acquires your DNA while at the same time there's a non-empty set of descendants that can be traced back to you.

Technically I'm sure that's true, but I can also believe, without doing the maths, that in the limit of infinite generations the probability tends to zero. Complete extinction of your line is one stable outcome, and father/motherhood of all people alive is another stable outcome, whereas anything in between is at best metastable.


I guess one question is: how much interbreeding with the rest of humanity takes place with isolated tribes?

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Re: 1545: "Strengths and Weaknesses"

Postby richP » Wed Jul 01, 2015 4:08 pm UTC

Jackpot777 wrote:As someone that decided not to have kids and has had a vasectomy, that puts that "strength" out of play for me.

Whether or not that makes me an asset or a liability to the company in the far future? I guess we'll just have to wait and see.


Liability: https://xkcd.com/583/

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Re: 1545: "Strengths and Weaknesses"

Postby Hiferator » Wed Jul 01, 2015 4:13 pm UTC

orthogon wrote:Technically I'm sure that's true, but I can also believe, without doing the maths, that in the limit of infinite generations the probability tends to zero. Complete extinction of your line is one stable outcome, and father/motherhood of all people alive is another stable outcome, whereas anything in between is at best metastable.

I was going to bring up the inevitable extinction of humankind, but your explanation is also interesting. Is the probability of a dynamical system to end up in a stable state always 1?

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Re: 1545: "Strengths and Weaknesses"

Postby ps.02 » Wed Jul 01, 2015 4:36 pm UTC

chris857 wrote:I guess one question is: how much interbreeding with the rest of humanity takes place with isolated tribes?

What's an isolated tribe? Sounds like a 20th-century concept. (Though even then, it seems Mary Matalin and James Carville could interbreed.)

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Re: 1545: "Strengths and Weaknesses"

Postby HES » Wed Jul 01, 2015 4:43 pm UTC

ps.02 wrote:
chris857 wrote:What's an isolated tribe?

The super-rich in their space stations, of course.
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Re: 1545: "Strengths and Weaknesses"

Postby Jackpot777 » Wed Jul 01, 2015 5:25 pm UTC

ajo4949 wrote:vasectomies are reversible, so "You never know!" ;)


Only under extreme duress!

Alternatively, that day has arrived and you are, in fact, an ancestor to no living human. Although I suppose the day won't definitively arrive until you die. But some day it will...strength!


I gain strength when I die. I feel like Kenobi right now.

Someone lightsaber me in half.

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Re: 1545: "Strengths and Weaknesses"

Postby freakish777 » Wed Jul 01, 2015 5:48 pm UTC

Interviewer: "What's your greatest weakness?"
Interviewee: "Sometimes I have trouble distinguishing fiction from reality."
Interviewer: "O... Okay, what's your greatest stren"
Interviewee: "I'M BATMAN!"

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Re: 1545: "Strengths and Weaknesses"

Postby mathmannix » Wed Jul 01, 2015 5:55 pm UTC

orthogon wrote:
Flumble wrote:I'm bothered by his strength statement. There may be a non-empty set of descendants that never acquires your DNA while at the same time there's a non-empty set of descendants that can be traced back to you.

Technically I'm sure that's true, but I can also believe, without doing the maths, that in the limit of infinite generations the probability tends to zero. Complete extinction of your line is one stable outcome, and father/motherhood of all people alive is another stable outcome, whereas anything in between is at best metastable.

Is this extendable to just the male line, i.e. your (if you are male) Y-chromosome? Are the only two possibilities with [very] long-term non-infinitesimal probabilities that either everyone alive will be my male-line descendant, or no one will be? (And yes, for the record, I already have a son...)
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Re: 1545: "Strengths and Weaknesses"

Postby RedwoodRhiadra » Wed Jul 01, 2015 6:42 pm UTC

ps.02 wrote:
chris857 wrote:I guess one question is: how much interbreeding with the rest of humanity takes place with isolated tribes?

What's an isolated tribe? Sounds like a 20th-century concept.


Even in the 21st Century, they still exist. See "Sentinelese".

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Re: 1545: "Strengths and Weaknesses"

Postby Pfhorrest » Wed Jul 01, 2015 6:50 pm UTC

I think maybe it's clearer looking at it backwards across time:

For any given set of humans (or any organism, but we're concerned with humans) at any point in time, there is some single human who is the most recent patrilineal ancestor of all humans alive ("Y-Chromosomal Adam"), and another who is the most recent matrilineal ancestor of all humans ("Mitochondrial Eve"). No other human besides them (and their ancestors) are the common ancestor of all humans.

At some point in the future, you will either be one of those figures (or an ancestor of one of them) to the population of that future time, or you won't, and if you're not, then you're neither a patrilineal or matrilineal ancestor of anyone = you are the ancestor of no one alive.

EDIT: On rereading I'm pretty sure that's a pile of bullshit I just wrote, but I only got an hour's sleep last night and I have food poisoning so I can't sort it out right now. Leaving it in place because I'd like to watch someone else tell me why exactly it's wrong and what the real explanation is.
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Re: 1545: "Strengths and Weaknesses"

Postby rmsgrey » Wed Jul 01, 2015 7:03 pm UTC

Another closely related phenomenon is that, if you go back long enough, everyone alive now will turn out to be descended from everyone alive then who has any descendents alive now.

That's different from the most-recent common ancestor, who is the last person who everyone currently alive was descended from, but will have been contemporary with people with some descendents and some non-descendents. You can be a common ancestor without ever having been a most-recent common ancestor.

Also, you can be someone's ancestor without their having inherited any of your genes...

Pfhorrest wrote:I think maybe it's clearer looking at it backwards across time:

For any given set of humans (or any organism, but we're concerned with humans) at any point in time, there is some single human who is the most recent patrilineal ancestor of all humans alive ("Y-Chromosomal Adam"), and another who is the most recent matrilineal ancestor of all humans ("Mitochondrial Eve"). No other human besides them (and their ancestors) are the common ancestor of all humans.


That last bit isn't right - the most recent common ancestor will usually be more recent than either of the specific-line MRCAs simply because they can claim descendents through any line.

Estimates for the human MRCA come in less than 5 000 years ago, while Mitochondrial Eve is 200 000 years ago.

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Re: 1545: "Strengths and Weaknesses"

Postby Vahir » Wed Jul 01, 2015 7:17 pm UTC

Pretty similar to this SMBC.

Spoiler:
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Re: 1545: "Strengths and Weaknesses"

Postby Pfhorrest » Wed Jul 01, 2015 7:48 pm UTC

Those kinds of interview questions make a lot more sense if you include the tacit "compared to others".

Everybody applying for this job is willing to perform services in exchange for currency. So besides that common strength, what is the greatest strength of yours in particular, which differentiates you from them? Likewise weaknesses.

Every job offers currency in exchange for the performance of services. So besides that common goal, why are you applying for this job in particular, instead of some other job? (In fact... she actually says "in particular" for that question in the SMBC, so there's no excuse for the applicant not getting it).

Etc. Though really the 5 years one has always stumped me. I used to think it was because I was hopeless and depressed and had no idea if I would be alive five years later, but now I've got a pretty solid life path and... I hope I'll be making more money for comparable work, in accordance with my job's raise schedule? That's really all I've got, as far as career plans go. (I've got a whole bunch of plans I'm waiting on that money to do in other parts of my life).


On the topic of MRCAs, can someone confirm for me: though there is one ancestor that is common to any given population of organisms, members of that population will also have a bunch of other uncommon (not shared) ancestors, right? So for a stupidly simple (and non-viable) toy example: a population of three people, two of one sex and one of another, have four kids between them, two by each possible pairing. That first generation dies out. The remaining population have a most recent common ancestor in their common parent, but half of them get the rest of their genes from a different ancestor than the other half.

So although I, a mostly-European mutt, have some ancestor in common with someone from the remotest of African tribes, we likely also have a whole bunch of other ancestors that differ between us. Yeah?

ETA: Is there such a thing as the MRCA of the populations from which a given individual descends? I.e. the MRCA of my parents? In my particular case I wonder how far back in time that would be, because though I'm mostly of European ancestry, my direct matrilineal ancestor of six generations ago was an African slave in the Dutch West Indies; so would that necessarily push the MRCA of my parents back to some time before humans left Africa? Or might the Dutch ancestry into which that line flows provide a more recent common ancestor with the rest of my European ancestors?
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Re: 1545: "Strengths and Weaknesses"

Postby armandoalvarez » Wed Jul 01, 2015 11:57 pm UTC

da Doctah wrote:In the event the human race dies out altogether, you'll simultaneously be the ancestor of all living humans and none of them.

(My strength is that I understand that any statement made to describe all members of the empty set is true. My weakness is that nobody else does.)

I think this is the only way this is true. If Randall means, "One day there will be no surviving humans, so I will not be the ancestor of all of them," then sure, that's true (barring humans figuring out how to survive whatever the actual ultimate fate of the universe is). If he means, "On the day the human race goes extinct, I will either be the ancestor to all living humans or none of them," then I think it's far from certain. If 50 years from now, you have ten descendants and some WMD destroys human life on the planet in an instant, than the statement isn't true. That's true of any number of years between now and infinity. Sure, there's a 99.9999(etc)% chance that it will work out to you being either the ancestor to all living humans or none, but it's not 100% true.

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Re: 1545: "Strengths and Weaknesses"

Postby rmsgrey » Thu Jul 02, 2015 1:33 am UTC

Pfhorrest wrote:On the topic of MRCAs, can someone confirm for me: though there is one ancestor that is common to any given population of organisms, members of that population will also have a bunch of other uncommon (not shared) ancestors, right? So for a stupidly simple (and non-viable) toy example: a population of three people, two of one sex and one of another, have four kids between them, two by each possible pairing. That first generation dies out. The remaining population have a most recent common ancestor in their common parent, but half of them get the rest of their genes from a different ancestor than the other half.

So although I, a mostly-European mutt, have some ancestor in common with someone from the remotest of African tribes, we likely also have a whole bunch of other ancestors that differ between us. Yeah?

ETA: Is there such a thing as the MRCA of the populations from which a given individual descends? I.e. the MRCA of my parents? In my particular case I wonder how far back in time that would be, because though I'm mostly of European ancestry, my direct matrilineal ancestor of six generations ago was an African slave in the Dutch West Indies; so would that necessarily push the MRCA of my parents back to some time before humans left Africa? Or might the Dutch ancestry into which that line flows provide a more recent common ancestor with the rest of my European ancestors?


Yeah, your MRCA with someone will, in general, have been contemporary with a bunch of other ancestors who aren't common. On the other hand, there will also be a point further in the past, where all your ancestors alive then are common.

Apparently, genealogists reckon that the European Age of Exploration has brought European ancestry to the rest of the world, making the MRCA someone in the first couple of millennia BC, though a sufficiently isolated tribe could mess that up.

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Re: 1545: "Strengths and Weaknesses"

Postby Dr What » Thu Jul 02, 2015 2:53 am UTC

"Where do you see yourself in five years?"
Eh... In... mirrors?

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Re: 1545: "Strengths and Weaknesses"

Postby gormster » Thu Jul 02, 2015 4:52 am UTC

I don't have any kids, so doesn't that mean I'm currently the ancestor to no living humans? Does "ancestor" include self in this sense?
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Re: 1545: "Strengths and Weaknesses"

Postby da Doctah » Thu Jul 02, 2015 6:41 am UTC

armandoalvarez wrote: If 50 years from now, you have ten descendants and some WMD destroys human life on the planet in an instant, than the statement isn't true.


But it'll be true the day after that. If there are no living humans, then I am the ancestor of all living humans, just as right now I am the ancestor of all living humans over thirty feet tall.

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Re: 1545: "Strengths and Weaknesses"

Postby Echo244 » Thu Jul 02, 2015 8:08 am UTC

Dr What wrote:"Where do you see yourself in five years?"
Eh... In... mirrors?


Mirrors 2.5 light years away? ;-D
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Re: 1545: "Strengths and Weaknesses"

Postby Neil_Boekend » Thu Jul 02, 2015 8:18 am UTC

"Where do you see yourself in 5 years"

• "Standing over your dead body, bloody axe still in hand"
• "Ruling all the world. All these pesky humans will be my slaves"
• "Doing your wife/mom"
• "Signing the sale of all the shares of this company to a hedge fund"
• "On hawaii, sipping a martini"
• "I won't be standing. I will be in my grave, having died of cancer"
• "Working for a competing company, shamelessly abusing the company secrets of this one"
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Re: 1545: "Strengths and Weaknesses"

Postby Flumble » Thu Jul 02, 2015 10:10 am UTC

"There is no such place. Seeing my future self would violate causality."

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Re: 1545: "Strengths and Weaknesses"

Postby tsotate » Thu Jul 02, 2015 10:28 am UTC

"Five years from right now? In a chair in front of a computer."

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Re: 1545: "Strengths and Weaknesses"

Postby The Moomin » Thu Jul 02, 2015 10:48 am UTC

Jackpot777 wrote:As someone that decided not to have kids and has had a vasectomy, that puts that "strength" out of play for me.

Whether or not that makes me an asset or a liability to the company in the far future? I guess we'll just have to wait and see.


Asset. You're less likely to be killed by a time-traveller trying to see what happens if they kill their grandparents, so you can potentially benefit the company with your work for longer.
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Re: 1545: "Strengths and Weaknesses"

Postby mathmannix » Thu Jul 02, 2015 12:43 pm UTC

Where do you see yourself in five years?

Don't say "doing your wife"...

The other good answer is "I'll be your boss." And of course, there's always beret guy's answer...
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Re: 1545: "Strengths and Weaknesses"

Postby armandoalvarez » Thu Jul 02, 2015 3:29 pm UTC

da Doctah wrote:
armandoalvarez wrote: If 50 years from now, you have ten descendants and some WMD destroys human life on the planet in an instant, than the statement isn't true.


But it'll be true the day after that. If there are no living humans, then I am the ancestor of all living humans, just as right now I am the ancestor of all living humans over thirty feet tall.

I said that the null set interpretation was the only interpretation that ensured that this is true.
Is your closing sentence something that is considered true in some formal logic system that I'm not aware of? I wouldn't consider myself the ancestor of all living 30 foot tall humans. That seems like dividing by zero.

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Re: 1545: "Strengths and Weaknesses"

Postby Pfhorrest » Thu Jul 02, 2015 6:33 pm UTC

Yes. Logically, every claim about all members of an empty set is true -- because there are zero members of that set, so it only has to be true of zero members for it to be true of all members, so if it's not true of any members, then it's true of zero members, and therefore true of all members.

For every thirty-foot human, I am that human's ancestor. But since there are no thirty-foot humans, I need be the ancestor of no thirty-foot human for that statement to be true.

All of my children are over thirty feet tall. Also, none of my children are over thirty feet tall. These are both true because I have no children.

The reason this is logically necessary is that "all x are F" is the equivalent of "there are no x which are non-F", which is true if there are no x at all. E.g. "all swans are white" means "there are no swans which are non-white"; and if there are no swans at all, then that is true.
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Re: 1545: "Strengths and Weaknesses"

Postby rmsgrey » Thu Jul 02, 2015 6:44 pm UTC

Pfhorrest wrote:The reason this is logically necessary is that "all x are F" is the equivalent of "there are no x which are non-F", which is true if there are no x at all. E.g. "all swans are white" means "there are no swans which are non-white"; and if there are no swans at all, then that is true.


It's preferred to do it that way for that reason, but it's not logically necessary - it's just more convenient to be able to say that "all x are F" and "no x are non-F" are always equivalent rather than having to say that they're equivalent so long as there is something which is x


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