Kautilya's Arthashastra 6.2.38

6.2.38

yadi vā paśyet "amitro me śaktiyukto vāgdaṇḍapāruṣyārthadūṣaṇaiḥ prakṛtīr upahaniṣyati, siddhiyukto vā mṛgayādyūtamadyastrībhiḥ pramādaṃ gamiṣyati, sa viraktaprakṛtir upakṣīṇaḥ pramatto vā sādhyo me bhaviṣyati, vigrahābhiyukto vā sarvasaṃdohenaikastho 'durgastho vā sthāsyati, sa saṃhatasainyo mitradurgaviyuktaḥ sādhyo me bhaviṣyati,
"balavān vā rājā parataḥ śatrum ucchettukāmaḥ tam ucchidya mām ucchindyād" iti balavatā prārthitasya me vipannakarmārambhasya vā sāhāyyaṃ dāsyati", madhyamalipsāyāṃ ca, ity evaṃādiṣu kāraṇeṣv amitrasyāpi śaktiṃ
siddhiṃ cecchet //

"That my enemy, possessed as he is of immense power, will yet in the near future, hurt the elements of his own sovereignty, by using contumelious language, by inflicting severe punishments, and by squandering his wealth; that though attaining success for a time yet he will blindly take himself to hunting, gambling, drinking and women; that as his subjects are disaffected, himself powerless and haughty, I can overthrow him; that when attacked, he will take shelter with all his paraphernalia into a fort or elsewhere; that possessed as he is of a strong army, he will yet fall into my hands, as he has neither a friend nor a fort to help him; that a distant king is desirous to put down his own enemy, and also inclined to help me to put down my own assailable enemy when my resources are poor; or that I may be invited as a Madhyama king,"--for these reasons the conqueror may allow his enemy to grow in strength and to attain success for the time being.

A king who is equal to his enemy in the matter of his sovereign elements shall, in virtue of his own righteous conduct or with the help of those who are hostile or conspiring against his enemy, endeavor to throw his enemy’s power into the shade; or if he thinks:--