From New York Times,  1 June 2003.

 Garry Trudeau at Trinity College, Hartford:

  The impertinent question is the glory and engine of human
inquiry. Copernicus asked it and shook the foundations of Renaissance
Europe. Darwin asked it and redefined humankind's very sense of
itself. Thomas Jefferson asked it an was so invigorated by the asking
that he declared one of our inalienable rights. 

  Two hundred years later, Martin Luther King asked it, and forced the
country to honor those rights. Daniel Defoe asked the impertinent
question and invented the novel.  James Joyce asked it and reinvented the
novel, which was promptly banned.  Jean-Paul Sartre asked it and
inspired Simone de Beauvoir, who asked it and inspired a whole
generation of women to question what they were doing with men like
Jean-Paul Sartre.  The Wright Brothers asked it and were ignored for
five years. Bill Gates asked  it and was ignored for five minutes,
which was long enough for him to dominate the industry. 

  Whether reviled or revered in their lifetimes, history's movers
framed their questions in ways that were entirely disrespectful of
conventional wisdom. Civilization has always advanced in the shimmering
wake of its discontents.