Sky - the limit ??

Sky i s t h e limit........Really ?? Do you know what Wikipedia wrote while defining sky, ''The sky is the part of the atmosphere or of outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons. During daylight the sky has the appearance of a deep blue surface, but this is the result of the air scattering sunlight. There is no "blue object" above the earth in any normal sense, so it is hard to say what object the sky is.'' Now tell me, when you put your limit to the sky, do you use your normal sense ? Funny.......Yaa ? ? ?