Srimad-Bhagavatam: Canto 1 - Chapter 1 - Verse 5
व्यास उवाचअस्त्येव मे सर्वमिदं त्वयोक्तंतथापि नात्मा परितुष्यते मे ।तन्मूलमव्यक्तमगाधबोधंपृच्छामहे त्वात्मभवात्मभूतम् ॥ ५ ॥
vyāsa uvācaasty eva me sarvam idaṁ tvayoktaṁtathāpi nātmā parituṣyate metan-mūlam avyaktam agādha-bodhaṁpṛcchāmahe tvātma-bhavātma-bhūtam
Śrī Vyāsadeva said: All you have said about me is perfectly correct. Despite all this, I am not pacified. I therefore question you about the root cause of my dissatisfaction, for you are a man of unlimited knowledge due to your being the offspring of one [Brahmā] who is self-born [without mundane father and mother].
In the material world everyone is engrossed with the idea of identifying the body or the mind with the self. As such, all knowledge disseminated in the material world is related either with the body or with the mind, and that is the root cause of all despondencies. This is not always detected, even though one may be the greatest erudite scholar in materialistic knowledge. It is good, therefore, to approach a personality like Nārada to solve the root cause of all despondencies. Why Nārada should be approached is explained below.