The ability to give credit is something of which Steven Wolfram is in very short supply!

Never mind Wolfram's obvious debt to John Conway, John von Neumann and Alan Turing, among many.

From an interview with Steven Wolfram (FT.com, 11 April 2003. "Lunch with the FT: Stephen Wolfram" by Simon London):

   Does he have any heroes, I ask, anyone in science whose work he really
   admires?
   The question is met with a long pause. 
   "I think Alan Turing would have discovered a lot of the things I have
   discovered if he had lived another 20 years. He was pointed very much in
   the same direction."
   A hero?
   "The more you learn about these people the more difficult it is to idolise
   them. Turing was much more of a hacker than I am. He liked putzing around 
   with things in a way that is somewhat different from my interests."
   How about (John) von Neumann, then?
   "I'm sure I would have greatly enjoyed meeting him. He was a smart man. But
   I would say he fundamentally missed deeper points in a whole series of areas
   in his haste to figure things out faster than other people. It was almost
   like science as a competitive sport. He skated too quickly over many areas."
   Isaac Newton is summarised as "an able man who did interesting work", while
   Charles Darwin "had the good feature of living basically a happy, quiet 
   life"  although "the core of what he did is better than some of the
   bandwagons he let himself climb on to".
   Any living scientist he especially admires? I suggest Stephen Hawking, the
   Cambridge astrophysicist, or Benoit Mandelbrot, whose work on fractals seems
   adjacent to Wolfram's own interests in complexity.
   Again, the reply is careful and considered.
   "Hawking I view as a fascinating personal study but as a scientist...well,
   I suppose he has done some decent-quality stuff. Benoit Mandelbrot I know 
   quite well and some of his work is quite important. In fact, I am one of
   his bigger promoters. I'm just not sure he has completely internalised 
   quite how important it is."