Can reasoning stand without citations?

Here we reach a fundamental methodological question.

Even suppose I have no citation, these reasons have force on their own.

The answer depends on the type of claim.

Suppose I argue:

Water expands when frozen.

I do not prove that by reasoning alone.

I need empirical evidence.

Likewise:

Political elites acted from economic motives.

Reasoning can make the hypothesis plausible.

But history asks:

Did they actually think this?

Reasoning alone cannot answer that.

Historical scholarship distinguishes between:

logical plausibility, and

historical proof.

A claim can be highly plausible yet still unproven if there is no evidence that the historical actors actually held those motives.