Tirukural/Chapter 59
581
These two: the code renowned and spies,
In these let king confide as eyes.
Let a king consider as his eyes these two things, a spy and a book (of laws) universally esteemed.
582
Each day, of every subject every deed,
'Tis duty of the king to learn with speed.
It is the duty of a king to know quickly (by a spy) what all happens, daily, amongst all men.
583
By spies who spies, not weighing things they bring,
Nothing can victory give to that unwary king.
There is no way for a king to obtain conquests, who knows not the advantage of discoveries made by a spy.
584
His officers, his friends, his enemies,
All these who watch are trusty spies.
He is a spy who watches all men, to wit, those who are in the king's employment, his relatives, and his enemies.
585
Of unsuspected mien and all-unfearing eyes,
Who let no secret out, are trusty spies.
A spy is one who is able to assume an appearance which may create no suspicion (in the minds of others), who fears no man's face, and who never reveals (his purpose).
586
As monk or devotee, through every hindrance making way,
A spy, whate'er men do, must watchful mind display.
He is a spy who, assuming the appearance of an ascetic, goes into (whatever place he wishes), examines into (all, that is needful), and never discovers himself, whatever may be done to him.
587
A spy must search each hidden matter out,
And full report must render, free from doubt.
A spy is one who is able to discover what is hidden and who retains no doubt concerning what he has known.
588
Spying by spies, the things they tell
To test by other spies is well.
Let not a king receive the information which a spy has discovered and made known to him, until he has examined it by another spy.
589
One spy must not another see: contrive it so;
And things by three confirmed as truth you know.
Let a king employ spies so that one may have no knowledge of the other; and when the information of three agrees together, let him receive it.
590
Reward not trusty spy in others' sight,
Or all the mystery will come to light.
Let not a king publicly confer on a spy any marks of his favour; if he does, he will divulge his own secret.