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Explain xkcd: It's 'cause you're dumb.
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Revision as of 23:07, 7 August 2012

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Russell's Teapot
Unfortunately, NASA regulations state that Bertrand Russell-related payloads can only be launched within launch vehicles which do not launch themselves.
Title text: Unfortunately, NASA regulations state that Bertrand Russell-related payloads can only be launched within launch vehicles which do not launch themselves.


Russell's Teapot is a philosophical argument that reflects on the difficulty of trying to prove a negative. It involves a hypothetical teapot orbiting a heavenly body, whose existence hasn't been proven, and states that it cannot be disproven (Somebody put it there secretly?). While an instrument could be theoretically engineered to pick out a teapot-sized object of any luminosity, the teapot would be very easy to confuse for other pieces of space debris, and the space to search is extremely massive; the task is thus akin to the proverbial search for a needle in a haystack.

Bertrand Russell devised this analogy "to illustrate that the philosophic burden of proof lies upon a person making unfalsifiable claims, rather than shifting the burden of disproof to others." As such, it is very often used in atheistic arguments.

"He wrote that if he were to assert, without offering proof, that a teapot orbits the Sun somewhere in space between the Earth and Mars, he could not expect anyone to believe him solely because his assertion could not be proven wrong." (Wikipedia)

Cueball is trying to settle the teapot argument by actually launching a teapot into space via a crowdfunding campaign.

"CubeSat-based design" refers to a type of miniaturized satellites that is made up of 10-centimeter cube units (here seemingly consisting of 3 units) and enables cost-effective means for getting a payload into orbit.

The title-text refers to Russell's paradox, also formulated by Bertrand Russell. Russell's paradox was a flaw found in naïve set theory where one could consider "the set of all sets that do not contain themselves" (a "set" is a mathematical term for a "group of things"). The paradox arises with whether this set, in turn, contains itself: if it does, then it cannot; if it doesn't, then it must. Similarly, like in the barber paradox, the vehicle which launches only vehicles which do not launch themselves is impossible: if the vehicle takes off, it must launch itself as well as the teapot, and thus can never be launched (without violating alleged NASA regulations, at least).

The barber paradox can be stated as follows: "Consider a town in which a man, the barber, shaves precisely those men who do not shave themselves. Does the barber shave himself?" Either answer, yes or no, leads to a contradiction. Sometimes the paradox is incorrectly stated, replacing "precisely those" with "only". Under that scenario, there is no paradox; the barber is merely unkempt.

A launch vehicle that does not launch itself is a contradiction in terms in a way that a barber who does not shave himself or a set that does not contain itself is not. NASA's regulation is not so much a paradox in itself as a ban on launching Bertrand Russell-related payloads.


[Cueball is standing in front of a blueprint labeled "CubeSat-Based Design", containing a satellite with a teapot in the top.]
[Caption below the panel:]
I'm crowdfunding a project to launch a teapot into orbit around the sun to settle the Russell thing once and for all.

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