The Vedic Scriptures
The following important Vedic scriptures will be presented here in brief:
Vedānta-sūtra
Nyāya-prasthāna, Śruti-prasthāna and smṛti-prasthāna are three sources of knowledge. Together they are called prasthāna-traya. The Upaniṣads are śruti-prasthāna; Bhagavad-gītā, Mahābhārata and the Purāṇas are smṛti-prasthāna; and the Vedānta-sūtra is nyāya-prasthāna. All transcendental knowledge must be based on śruti, smṛti and nyāya (logic and sound arguments). Therefore, in philosophical discussions and debates, statements are substantiated by quoting verses from Upanisads, Vedānta-sūtra, etc. In the Bhagavad-gītā (13.5), the Supreme Lord says: brahma-sūtra-padaiś caiva hetumadbhir viniścitaiḥ - "Knowledge of the goal of life is especially explained in the Vedānta-sūtra, with all the evidence regarding cause and effect." That is why the Vedānta-sūtra is known as nyāya-prasthāna.
The Vedānta-sūtra - also called the Brahma-sūtra - was composed by Vedavyāsa, an incarnation of Śrī Nārāyaṇa, the Supreme Lord. Vedānta means "the end of knowledge", i.e. transcendental knowledge of the Absolute Truth in its three aspects brahman, paramātmā and bhagavan. The main purpose of the Vedānta-sūtra and the discussions in the Upaniṣads is to underline the personal aspect of the Absolute Truth. The Vedānta-sūtra summarises the philosophical insights of the Upaniṣads. A definition of sūtra is given in Skanda-Purāṇa: "a sūtra is an aphorism that expresses the essence of all knowledge in a few words. It must be universally applicable and flawless in its linguistic presentation."
The Vedānta-sūtra consists of four adhyayas (chapters), each divided into four pādas (subdivisions). The topics of each subdivision of aphorisms are elaborated with reference to pratijña (assertion), hetu (reason), udaharana (proof by examples), upanaya (correlation), nigamana (conclusion, based on authoritative statements of the Śāstra). Pratijña at the beginning of the Vedānta-sūtra is: athāto brahma-jijñāsā ("now is the time to ask questions about the Absolute Truth"). This indicates that the work was written with the purpose of realising the Absolute Truth.
The aphorisms of the Vedānta-sūtra are not easy to understand and have been misinterpreted by impersonalist philosophers (mayavadis) who deny the Personality of Godhead and the relationship of living beings to the Supreme Lord. Śrīla Vyāsadeva, the author of the Vedānta-sūtra, himself composed a commentary on the Vedānta-sūtra known as the Śrīmad-Bhāgavatam or Bhāgavata-Purāṇa. When an author of a work himself writes a commentary on his work, there is no need to be misled by interpretations from other authors.
See Śrīla A.C. Bhaktivedanta Swami Prabhupada's commentary on a verse in the Caitanya-Caritāmṛta.