What is an “abstract philosophical statement”?

An abstract philosophical statement is a proposition dealing with a general concept at a theoretical level rather than making a claim about a particular historical event.

For example:

“Freedom is inherently valuable.”

or:

“True equality requires equal power.”

These are philosophical propositions.

They can be supported or defended, but they require philosophical reasoning and argument rather than simply historical evidence.

Compare:

“Formerly enslaved people faced severe economic disadvantages after emancipation.”

That is a historical claim.

You can investigate it through:

• census records;
• land records;
• contracts;
• government reports;
• contemporary testimony;
• historians' research.

So my phrase:

“rather than merely being an abstract philosophical statement”

did not mean philosophical statements cannot be supported.

It means they require a different kind of justification.