Good question. i will try my level best to answer this question. i will be happy if it gives you satisfaction.Now we will go to the answer.
my answer: Your question is this: 1. What are Prasthanatrayi? 2. How they are important to understand the philosophy of shashtras? we will see in detail.
1. what is Prasthanatrayi?
Vedanta philosophy bases itself mainly upon three sets of texts, called Prasthana Trayi.These are the Upanishads (Sruti Prasthana),
the Bhagavata Geeta (smriti Prasthana)
and the Brahma sutras of Badarayana (Nyaya Prasthana).
The Literal meaning of the word "Prasthan" is Departure. Departure to achive the supreme goal of one's living, Departure towards the Brahman, Departure from the physical world etc.,
The Prasthantrayi refers to three holy books such as the Upanishads, the Brahma-Sutra and the Bhagavad Gita. These three books are collectively known as the Prasthantrayi or the Prasthantrayam. They form the Scriptural Trinity of the Hinduism.The Prasthanatrayi consists
1.The Brahma Sutras, known as Nyaya prasthana,
2.The Upanishads, known as Upadesha prasthana, and
3.The Bhagavad Gita, known as Sadhana prasthana
2. How they are important to understand the philosophy of shashtras?
Badarayana (Ved Vyasa) was a great scholar with exceptional erudition. He initiated the challenging task of systematizing the Vedas. He meticulously studied the vast philosophical doctrines of the Upanishads. He pioneered the efforts to simplify the Upanishadic philosophy what we know as the Vedanta.
The result of his efforts was one of the most illustrious works on the Vedanta. Badarayana’s work is known as Brahma-Sutra.The Brahma-Sutra is also referred to as Vedanta-Sutra or Uttar-Mimamsa-Sutra.
The Bhagavad Gita is a part of the great epic, the Mahabharat.The Mahabharat, authored by the great sage Veda Vyasa, is an epic that vividly depicts the different facets of human life. There are unsurmountable aspirations, ceaseless activities and inspiring achievements in Mahabharat. Amongst all these shine out the philosophy of the Bhagavad Gita.
These three types of literature is the main sourse of knowledge. or in other words it's the summary or conclusion of the vedic knowledge Ocean(Shastras).Advaita Vedanta is a sub-school of the Vedānta school of Hindu philosophy. Other major sub-schools of Vedānta are Dvaita and Viśishṭādvaita. Advaita is often called a monistic system of thought. The word "Advaita'' essentially refers to the identity of the Self (Atman) and the Whole (Brahman). The key source texts for all schools of Vedānta are the Prasthanatrayi – the canonical texts consisting of the Upanishads, the Bhagavad Gita and the Brahma Sutras.
All of the above philosophies of Hinduism have one thing in common. They are all derived from and consistent with the triad of authentic Hindu scriptures known as Prasthan Trayi, namely, Upanishads, Bhagwad Gita, and Brahm Sutra. They include the essence of all the ancient Hindu scriptures, namely, Vedas, Upanishads, various sutras, various smrutis, all the Purans, Mahabharat, and Ramayan. Number wise Hindu scriptures are not just a few texts but they are hundreds in numbers, consisting of hundreds of thousands of verses (shloks) and short sentences (sutras), and all of them are in Sanskrit or other vernacular languages derived from Sanskrit.
It is difficult to study single-handedly and understand them all individually. This explains why there are many interpretations, explanations, and commentaries just about one single Truth and the five fundamental eternal realities in Hinduism.The beauty of Hinduism is that it allows complete religious freedom at the same time teaches to develop the utmost tolerance for others’ belief.The Philosophical thoughts gives importance to our daily life.
The Satyam (the truth), Shivam (the greatness), and Sundaram (the beauty) of Hinduism is that leaving aside its religious and philosophical aspects, and keeping one’s own faith or belief in one’s own religion, religious practices, religious philosophy, and the choicest deity of worshiping, one can still study, understand, and practice the universal, natural, and humanitarian aspect of it to bring the mental peace, world peace, and the heaven, paradise, or swarg on the earth.
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