One point in Vaishnava philosophy that is very different from what most historians believe is the eternality of the Vedas. We believe the Vedas are eternal, being present since the beginning of time. However, when historians study archaeological evidence, it appears that the Vedas although very ancient passed through a process of evolution and change. How is that?
The point is that indeed, the Vedas passed through a process of transformation about 5000 years ago, but it was different from what is believed by most historians.
The point is that in the previous Dvapara-yuga, the knowledge of the Vedas was practically destroyed, with the followers of the Vedas degenerating into six separate schools, none of which conserved the proper understanding of the scriptures.
These six philosophical systems, or sad-darshanas are what most historians interpret as being the classical or orthodox Vedic schools, simply because they are the furthest we can study based on archaeological findings. The true classical Vedic schools are much further in the past, and their knowledge was transmitted only orally, making it impossible to trace apart from the history that is described in the Vedas themselves.
As mentioned, the sad-darshanas are actually late schools of thought that formally accept the Vedas, but don’t accept their ultimate meaning.
These six philosophical systems are:
1- The Nyāya system, by Gautama Ṛṣi,
2- The Vaisesika system, by Kaṇāda Ṛṣi,
3- The philosophy of Sāṅkhya, by the atheistic Kapila,
4- The system of mystic yoga, by Patañjali,
5- The philosophy of Karma-mīmāṁsā, by Jaimini,
6- The philosophy of impersonalism, propounded by Aṣṭāvakra (and later Sankaracarya).
Originally, these six philosophical systems were different parts of a unified system of understanding of the Vedas, but with time the scholars started disagreeing and the systems became separated, with none of them having a complete view of the goal of life.
The resultant six philosophical systems are predominantly atheistic, studying different aspects of the material nature separately from the Supreme Lord. Logic, meditation, and so on are part of our spiritual studies and practice, but when disconnected from Krsna they become just materialistic philosophies that have little purpose in bringing one back to Godhead.
1- The Nyaya system deals with reasoning and logic, setting up rules of philosophical debate, identifying subjects for discussion, etc. The main concern is in establishing the conditions for obtaining correct knowledge, and the means of receiving knowledge, analyzing the nature and source of different types of knowledge to determine their validity or non-validity, and so on. Logic has a very important role in the study of the Vedanta Sutra, for example, since it is full of logical arguments that lead us to a conclusive understanding of the Upanisads. However, when taken separately, logic becomes just a tool for debating and exerting one’s ego.
2- The Vaisesika system, propounded by philosophers like Gautama and Kaṇāda, studies the material world in great detail, determining its causes and effects in order to destroy material suffering. They conclude that ignorance is the root cause of all misery, and believe that one can attain liberation only by cultivating the right understanding of reality. The main focus in this school is on studying the cause and effects of the material creation, and especially the material elements. Their conclusion, however, is that the atomic combination of material elements is the original cause of creation.
3- The Sāṅkhya system is an analytic study of the material elements. Although it bears the same name as the ancient system introduced by Lord Kapila the son of Devahuti (narrated in the 3rd canto of Srimad Bhagavatam), which has existed since the beginning of the current day of Brahma, the modern system was propounded by another Kapila. While the original Sāṅkhya system taught by Lord Kapila studies the material elements with the ultimate purpose of ascending to a platform of devotional service, the system propounded by the atheistic Kapila discards the existence of God and concludes that since the material world is ultimately illusory, the causes of this material manifestation are also illusory, and thus the ultimate goal is a form of voidism.
4- The process of mystic yoga, is offered in the Vedas as a bonafide process of self-realization. Krsna himself describes the system of asthanga-yoga in the Bhagavad-Gita. Originally, yoga means to link our consciousness with the Supreme Personality of Godhead, reviving our original spiritual identity. The system that is counted amongst the six philosophical systems is the patanjala-yoga, propounded by Patañjali in his Patanjala-yoga-sutra. This system is focused on examining the nature of the mind, its workings, the impediments it creates, the causes of material suffering, and so on. The ultimate goal in this system is kaivalya, or impersonal liberation.
5- The system of Karma-mīmāṁsā was propounded by a sage called Jaimini. This is a philosophical school that stresses fruitive activities. For them, the results of one’s material activities are supreme, and if there is a God, he is nothing more than an order supplier, who just delivers the results of one’s karma. According to this system, there is no need to become a devotee of the Lord. One should just follow moral principles and perform pious activities, and thus be happy in this world by receiving the results of his good karma.
6- The last system is the interpretation of the Vedanta propounded by impersonalists such as Aṣṭāvakra and more recently by Śaṅkarācārya. They reject the idea of the Absolute truth being ultimately a person and accept the impersonal Brahman effulgence as the cause of everything. According to their theory, the material manifestation is temporary and unreal, and only the Brahman effulgence is reality. Just like in the patanjala-yoga system, their ultimate goal is impersonal liberation, merging into the light of the Brahmajoti.
Vyasadeva contested these six systems, restoring the original teachings of the Vedas. At that point, different books of the Vedas were still being transmitted by disciplic succession, but their true meaning was lost. Vyasadeva compiled and organized all this knowledge, and gave their meaning in books such as the Vedanta Sutra and the Srimad Bhagavatam.
As Srila Baladeva Vidyabhusana mentions in his Govinda Bhasya, during the past Dwapara Yuga, the Vedas were destroyed. At the time, many foolish philosophers propounded different incorrect interpretations of the Vedas, and the real spirit of the scriptures was almost lost. Some were teaching that the ultimate goal of life was to act piously to enjoy the results of good karma. Some sustained that the fruits of good karma, such as elevation to the high planets are eternal, with some having the audacity of saying that Lord Vishnu Himself is bound by the laws of karma. Others were saying that there is no God and the jivas (the individual souls) and prakrti (the material energy) act independently, without any superior control. Some were propounding that in reality all sous are God, and we become free from the cycle of birth and death when we understand our real identity as part of the Supreme Brahman. Others were saying that the souls are a reflection of God, or separated fragments of God, and so on. Answering the prayers of Lord Brahma and other demigods to come as an incarnation and dispel all these speculations, restoring the actual meaning of the Vedas, the Lord appeared as Krsna Dvaipayana Vyasa. He divided the Vedas and wrote the Vedanta Sutra in order to explain the real meaning of the scriptures.
The original palm leaves written by Vyasadeva were then copied and distributed, and copies were made out of the copies. Thus, different sets of leaves with writings that are still available nowadays were written at different points in history, some one thousand years ago, some at two or three thousand. None of these sets are the original writings of Vyasa, but just copies that survived. All these copies have a history that goes all the way back to the original writings of Vyasa, but this is impossible to trace archeologically.
Scholars take all this information and try to make sense of it, creating different theories for the appearance of the Vedas, but if we accept the version given in the Vedas themselves, this is the history.