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Explain xkcd: It's 'cause you're dumb.
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Strengths and Weaknesses
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.
Title text: 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.


Ambox notice.png This explanation may be incomplete or incorrect: May need some more detail on the likelihood of becoming the ancestor of all living humans. Explain the title text.

Here Cueball is in a job interview and is being asked prototypical job interview questions by Ponytail, "What is your greatest weakness?", "What is your greatest strength?" and "Where do you see yourself in five years?"

In a roundabout way, Cueball answers that he is a living organism, and as such he has inherent flaws which could cause him to die. This is a reference the fact that biological system are "messy" and are not always optimal in design or operation. For example cancer is a disease where the cellular machinery that governs cell replications breaks down and prolific cell division happens, endangering the organism (tumors). While this is true weakness it is also a weakness of all humans and is not likely to help the interview determine if the candidate is right for the job.

For the second question the character answers that he will one day be the ancestor to all living humans or none of them. As you go farther and farther into the future the ratio of people alive will either go to 0% or 100% of the descendants of the character. The most recent common ancestor (MRCA) for humans is estimated to have been alive between 2,000 and 4,000 years ago. If the MRCA's ancestors are traced back, the Identical Ancestors Point can be found, at which point the entire population are either ancestors all living humans, or no living humans. For humans, this point is estimated to be between 5,000 and 15,000 years ago.

Assuming there will still be humans 15,000 years from now, it is highly unlikely that someone living today will be their ICA, as the gene pool will probably scatter into isolated sets via space travel, preventing that from happening again. While this could be considered his greatest personal strength in the bigger picture of the life cycle of the universe, this answer likely does not help the interviewer determine whether he is suitable for the role.

For Cueball to be the ancestor to all living humans within 5 years means that all the humans who are not his children (or grandchildren), must have died in a near total extinction of the human race. Given that Cueball is not his own ancestor, he too must have died. His apparent optimism about the possibility of this occurring is therefore somewhat confusing.

The overarching joke is that Cueball assumes that the interviewer is assessing his fitness as an organism from a genetic perspective rather than his fitness for performing a particular job. The biggest limitation on fitness is survival time and mortality.

The title text takes this further, equating producing offspring during an interview (which would be awkward for all involved) with something that may actually help assess a candidate's efficacy as an employee, namely writing out a sorting algorithm on the spot (see 1185: Ineffective Sorts, especially the bottom left panel).


[Ponytail is shown sitting on a swivel chair, to the left of a desk.]
Ponytail: What would you say is your biggest weakness?
[The view expands to show Cueball sitting on another swivel chair, on the opposite side of the desk.]
Cueball: Probably that I'm a giant tangle of parts that don't always work right, so I can die easily.
Ponytail: Biggest strength?
Cueball: There will come a day when I'm either an ancestor to all living humans, or to none of them.
Ponytail: Where do you see yourself in five years?
Cueball: Probably not the ancestor of all living humans yet. But you never know!

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