The phrase "accepts a theory" is correct and usable in written English.
It can be used when discussing the acknowledgment or endorsement of a particular theory in a scientific, academic, or philosophical context.
Example: "The researcher accepts a theory that explains the phenomenon observed in the experiment."
Alternatives: "endorses a theory" or "acknowledges a theory".
When one accepts a theory, one has a belief, and also a commitment.
One accepts a theory as true as a means to developing a better theory.
It could be that he accepts a theory of knowledge relevantly similar to that of David Lewis on which one must rule out all relevant, or in van Inwagen's case "real," possibilities, but there is another way to take it.
A scientist accepts a theory based on empirical evidence that adequately validates the overall concept his/her views are not to be tainted by opinions, personal religious convictions, or beliefs (Smith 1994).
But what I do know is that no managers should accept a theory about business unless they can be confident that the theory's advocates are working off an unbiased data set.
(3) Impartiality: The only grounds for accepting a theory are its relations to the evidence.
One reason scientists accept a theory is because it explains many, often diverse, observations.
On this account, even an ideally rational person might accept a theory without being able to determine its ontological commitments.
Thus, to have good reason to accept a theory is to have good reason to believe in the existence of those entities it postulates.
The only questions are philosophical: Can the concepts that such theories aim to formalize be explained, and do we have good reason to accept a theory formulated in these terms?
If the aim is to explain the rationality of accepting a theory on the basis of actual observations, then almost the entire theory would need to be taken as implicitly defining theoretical terms.
