Methodological question vs historical question

Methodological question:

What kind of evidence is needed before we attribute motives to some one?

This is a question about standards of proof.

Example:

Is a speech enough?

Is a private letter needed?

Is one document enough or several?

The question is not yet asking what some one thought. It is asking how historians should decide what he thought.

Historical question:

What evidence exists regarding one's motives?

Now we are looking for actual evidence:

speeches,

letters,

cabinet discussions,

newspaper interviews,

memoirs.