简介:Thefamousphysicistmadeforhisscholarsthisriddle.Afellowencounteredabearinawasteland.Therewasnobodyelsethere.Bothwerefrightenedandranaway.Fellowtothenorth,beartothewest.Suddenlythefellowstopped,aimedhisguntothesouthandshotthebear.Whatcolourwasthebear?