Now we will no longer concede so easily that anyone has the truth; the rigorous methods of inquiry have spread sufficient distrust and caution, so that we experience every man who represents opinions violently in word and deed as any enemy of our present culture, or at least as a backward person. And in fact, the fervor about having the truth counts very little today in relation to that other fervor, more gentle and silent, to be sure, for seeking the truth, a search that does not tire of learning afresh and testing anew.
The end and aim of spying in all its five varieties is knowledge of the enemy; and this knowledge can only be derived, in the first instance, from the converted spy. Hence it is essential that the converted spy be treated with the utmost liberality.
Wars, therefore, are to be undertaken for this end, that we may live in peace, without being injured; but when we obtain the victory, we must preserve those enemies who behaved without cruelty or inhumanity during the war.