I want to know is there a unite definition of "science"? my guess is "NO"!
What do philosophers means by science that they can't define it?
what is its difference with knowledge?
Science can be defined by its method. In short, the method is:
A typical science is physics, the method of physics is exemplified by quantum mechanics (QM):
Scientific knowledge is the content of accepted scientific theories. But in general, the scope of 'knowledge' is considered much broader than scientific knowledge. In any case I consider a necessary condition for knowledge the ability to provide reasons for knowledge claims.
For a nice introduction to the different aspects of knowledge see also the beginning of Aristotle's 'Metaphysics'.
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