These words were once put by a Dutch innkeeper on his signboard, as a satirical inscription over the representation of a churchyard. We need not inquire whether they hold of men in general, or particularly of the rulers of States who seem never to be satiated of war, or even only of the Philosophers who dream that sweet dream of Peace. The author of the present Sketch, however, would make one remark by way of reservation in reference to it. It is well known that the practical politician looks down, with great self-complacency, on the theoretical Politician, when he comes in the way, as a mere pedant whose empty ideas can bring no danger to the State, proceeding as it does, upon principles derived from experience; and the theorizer may, therefore, be allowed to throw down his eleven skittle-pins at once, while the sagacious Statesman who knows the world, need not, on that account, even give himself a turn! This being so, should any matter of controversy arise between them, the practical Statesman must so far proceed consistently and not scent out a danger for the State behind the opinions of the theoretical thinker, which he has ventured in a good intent publicly to express. By which ‘saving clause,’ the Author will consider himself expressly safeguarded against all malicious interpretation.
Immanuel Kant, “‘Perpetual Peace: A Philosophical Sketch’ (1795)“, i.1