Though fraud in all other actions be odious, yet in matters of war it is laudable and glorious, and he who overcomes his enemies by stratagem is as much to be praised as he who overcomes them by force.
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.
To demand of strength that it should not express itself as strength, that it should not be a desire to overcome, a desire to throw down, a desire to become master, a thirst for enemies and resistances and triumphs, is just as absurd as to demand of weakness that it should express itself as strength.