What is the/a definition for the term 'context'?
The term is used everywhere, and the dictionaries only give a description of it's meaning.
Definitions for other terms such as concept, perspective, etc, should be derivable from such a definition of 'context'.
To make my question clearer, this question about alternative logics contains the following phrase: "it is rational for anybody that if P is correct then P or Q is correct too": my contention is that this statement is entirely incorrect since the context in which P is correct or not, is not evident, and therefor nothing can be said about "P or Q". I would assume that somehow a context is included tacitly (for the rational bit at least), but for any such tacit context I would be able to propose a context in which P is incorrect or does not apply at all. I would think for any form logic the "context" in which it's statements applies should be well defined, and this brings me to my question: what is a "context"?
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Just a bit more on the P/Q-thing since answers seems to focus on that:
if P is the statement "the sky is blue" and Q is "it is a starry night"
then the 'wrongness' due to the lack of context is clear. The context must give a definition-space in which the relationship between P and Q exists (going into epistemology here).