OK, that makes a bit more sense, even if it is a bit cruel to set kids a task that by definition cannot be completed. Wouldn't it be simpler just to explain the concept to them?

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There is a growing tendancy to think of Man as a rational, thinking being, which is absurd.- Marvin the Martian.

It's gotten to the point where careful investigation is needed just to tell parody from reality. I think that means reality is broken.- Noclevername.