natural science vs philosophy

natural science

noun
  • Any science involved in studying phenomena or laws of the physical world: physics, chemistry, biology, astronomy, and so on. 

philosophy

noun
  • A view or outlook regarding fundamental principles underlying some domain. 

  • An academic discipline that seeks truth through reasoning rather than empiricism. 

  • A general principle (usually moral). 

  • A calm and thoughtful demeanor; calmness of temper. 

  • A comprehensive system of belief. 

  • The love of wisdom. 

How often have the words natural science and philosophy occurred in a corpus of books? (source: Google Ngram Viewer )