What is work of buddhi(intelligence)?

Question

For E.g In scriptures it is said that buddhi(intelligence) makes decision(निस्चय).But I think it must have broader meaning.

What are the other characteristics of buddhi(intelligence)?

Answer 1

Buddhi is one of the 17 components that form the Linga Deha/Sukshma Sarira (subtle body).

My subtle body (Linga Deha) arises from the union of the five Jñânendriyas, the five Karmendriyas (organs of action), the five Pranas and the mind and Buddhi, these seventeen elements. And the Prakriti that resides there is divided into two parts; one is pure (Suddha Sattva) Mâyâ and the other is the impure Mâyâ or Avidyâ united with the Gunas. By Mâyâ is meant She, who, without concealing Her refugees, protects them. When the Supreme Self is reflected on this S'uddha Sattva, Mâyâ, He is called Îs'vara.

Devi Bhagavatam 7.32

If we think the body as a chariot then Buddhi (intellect) has been compared to the charioteer in the scriptures.

That is Brahma and My Nature, too. This is the Goal of "Not this, Not this" the Vedânta words. This Self is not born nor It dies. It does not live also, being born. (But it remains constant, though It is not born). This Self is unborn, eternal, everlasting, ancient. It is not killed, when the body is killed. If one wants to kill it or thinks It as slain, both of them do not know; this does not kill nor is it killed. This Âtman, subtler than the subtlest, and greater than the greatest, resides within the cave (the Buddhi) of the Jîvas. He whose heart is purified and who is free from Sankalpa and Vikalpa (doubt and mental phenomena), knows It and Its glory and is free from sorrows and troubles. Know this Âtman and Buddhi as the charioteer, this body as the chariot, and the mind as the reins. The senses and their organs are the horses and the objects of enjoyments are their aims. The sages declare that the Âtman united with mind and organs of senses enjoys the objects. He who is nondiscriminating, unmindful, and always impure, does not realise his Âtman; rather he is bound in this world. He who is discriminating, mindful, and always pure reaches the Goal, realises the Highest Self; and he is not fallen again from That.

Devi Bhagavatam 7.34

Same thing is mentioned in the [Katha Upanishad 1.3.3]1:

आत्मानँ रथितं विद्धि शरीरँ रथमेव तु ।
बुद्धिं तु सारथिं विद्धि मनः प्रग्रहमेव च ॥ ३ ॥

ātmānam̐ rathitaṃ viddhi śarīram̐ rathameva tu |
buddhiṃ tu sārathiṃ viddhi manaḥ pragrahameva ca || 3 ||

3. Know the atman as the lord of the chariot, the body as only the chariot, know also intelligence as the driver; know the minds as the reins.

From this analogy it should clear what is the role of Buddhi. Buddhi has complete control over both the mind and the body.