why so many languages

wouldn't it be better if there was only one language like c++ or c#
then programmers could spend their time mastering that language
instead of re-learning the basics of another language every few years

>>32
Here in the 21st century we have made great strides in the state of the art.  No longer can we say that "real programmers" will write FORTRAN in any language.  Oh, no, siree!  Nowadays, "real programmers" will write 'C' in any language.

That is what such lowest common denominator cross-language approach leads to -- and you'd still be left rather high and dry by the time you went the small step from, say, Java to Scala.