When he thinks that the army he has hired is greater than his hereditary army; that his enemy's hereditary army is small and disaffected, while the army his enemy has hired is insignificant and weak; that actual fight is less than treacherous fight; that the place to be traversed and the time required do not entail much loss; that his own army is little given to stupor, is beyond the fear of intrigue, and is reliable; or that little is the enemy's power which he has to put down, then is the time for leading the hired army.