Seems to me that James is simply saying that Critical Thinking
   is one thing, Science is another thing. Distinct. They may have
   overlap. They might have a LOT of overlap. But one does not
   substitute fully for the other. You can have Science without
   Critical Thinking just as you can have Critical Thinking without
   Science.

   Thankfully, there is a strong correlation between the two but
   they still remain distinct in many ways.