The form and development of Putnam s scientific philosophy go through a complex academic course, from establishing scientific realism, to developing the useful and discarding the useless, to protecting internal realism, and to returning to life and practice.

The internal realism s theoretical origination can be traced back to Kantism,and it is deeply affected by the thoughts of Tarski, Goodman, Davidson, and so on, and it comes more directly from the criticism of metaphysical realism.

The contemporary research on Epistemology has taken on a new look in which the internalism-externalism debate on epistemic justification stands out as a central controversy.

There are two different view about the essence of dualism of practical reason in western ethics: internalism and externalism,the former is more reasonable.

, the distinction between agent-relative and agent-neutral values and the distinction between internalism and externalism, the author classifies and evaluates different Western theories of practical rationality under four major categories: agent-relative externalism, agent-relative internalism, agent-neutral internalism and .

The strengthening theorty of mechanism","the internal theory of spiritualism"and "the theory of knowledge"are deeply compared and analyzed from different angles,which greatly have influenced our foreign language teaching,so that we can fully understand and approach the law of foreign language teaching ,and raise the idea of foreign language teaching reform.