Therefore the nature of the hostile country, its fortified places, the allies of the enemy, their prosperity and adversity, must be ascertained by spies.
तस्माद् देशे च दुर्गे च शत्रुमित्रबलेषु च। नित्यं चारेण बोद्धव्यं स्थानं वृद्धिः क्षयस्तथा॥