Basic Marx quote --- help!

[Max B. Sawicky]

Does anyone happen to know the exact wording -- and the source -- for the
quote where Marx says something to the effect of, "philosophers have to this
point only described the world, but the point it to change it"? Need it for
a talk today. THANKS!
CK
>>>>>>>

I think that quote has been totally lost on
the marxists here.

mbs