Three Fundamental Principles
In the enquiry which follows I have kept to three fundamental principles:
 always to separate sharply the psychological from the logical, the subjective from the objective
 never to ask for the meaning of a word in isolation, but only in the context of a proposition
 never to lose sight of the distinction between concept and object
From the introduction to The Foundations of Arithmetic frege1884.


2. Analyticity and A Priority
Now these distinctions between a priori and a posteriori, synthetic and analytic, concern, as I see it, not the content of
the judgement but the justification for making the judgement...
When a proposition is called a posteriori or analytic in my sense, this is not a statement about the conditions, psychological,
physiological, and physical, which have made it possible to form the content of the proposition in our consciousness; nor
is it a judgement about how some other man has come, perhaps erroneously, to believe it true; rather, it is a judgement about
the ultimate ground on which rests the justification for holding it to be true.
The Foundations of Arithmetic frege1884, §3.

87. The Analyticity of Arithmetic
I hope I may claim in the present work to have made it probable that the laws of arithmetic are analytic judgements and consequently
a priori/.
Arithmetic thus becomes simply a development of logic, and every proposition of arithmetic a law of logic, albeit a derivative
one.
The Foundations of Arithmetic frege1884, §87.

