Incontestable

Does it follow that I reject all authority? Far from me such a thought. In the matter of boots, I refer to the authority of the bootmaker; concerning houses, canals, or railroads, I consult that of the architect or engineer. For such or such special knowledge I apply to such or such a savant. But I allow neither the bootmaker nor the architect nor the savant to impose his authority upon me. I listen to them freely and with all the respect merited by their intelligence, their character, their knowledge, reserving always my incontestable right of criticism and censure.

This fact is incontestable.

That he was the greatest 100m runner of his generation was incontestable.