Sri Krishna in Bhagavad-Gita explains Arjuna in regard to the Four Varnas. He says “Chatur-Varnam Maya Shrustam, Guna Karma Vibhagasha” - I created the four varnas namely Brahmana, Kshatriya, Vyshya and Sudra according to the prominence of Gunas in them and the natural aptitude they have towards the action they do. The Guna that is told here is not the character but the Prakriti (nature) of the individual containing the amalgamation of the trigunas i.e. Sattva, Rajas and Tamas.
An individual who has Satva Guna is categories as Brahamana (Teacher/Scholar)
An individual who has Satva and Rajas with Rajas in prominence is a Kshatriya (Ruler/Administrator)
An individual who has Rajas and Tamas with Tamas in prominence is a Vaisya (Merchant/Tradesmen)
An individual who has Tamo Guna is categories as Sudra (Worker/Craftsmen)
In the Shanti Parva of Mahabharata, Yudhisthira describes a Brahmin as an individual who is truthful, forgiving, and compassionate. He clearly mentions that a Brahmin cannot be a Brahmin just because he is born to a Brahmin family, nor is a Shudra a Shudra because his parents are Shudras. Manusmrti (11.157) says, “Just as a wooden toy elephant cannot be a real elephant and a stuffed deer cannot be a real deer, even so, without the knowledge of Scriptures and Vedas and not having developed the intellect an individual even if born to a Brahmin cannot be considered a Brahmin”. According to the Dharmasutra of Apastamba, by birth every individual is a Shudra. It is only by knowledge, upbringing, behaviour and wellness that one becomes a Dvija the “twice born”.
This system of division of labour was to help the individuals in inter dependence to strive for the existence of society. But this division of labour has so much so divide our society that we give much credit to Engineers and Doctors but we care less to Farmers and Soldiers. A road layer and a sanitary cleaner are as important to society as space scientist and research doctor. We usually tell our children to study well and give the instance of becoming a road layer and a sanitary cleaner if they don’t study well in this way we bring the division of labour in them. Instead we can tell them by studying well one can serve the society better than a road layer and a sanitary cleaner even though those work are divine and are necessary for society.
Karma is not the work that we do but is the latent desires that the souls have carried from their past lives. If suppose an individual who had been in the category of Brahamana and had a desire of having lordship over others as a ruler but could not fulfil his desire in that life, he will be given an opportunity by Supreme in the future life in letting him to take birth in a Kshatriya family. The proof for this is in “Atmasamyama Yoga” of Bhagavad-Gita in Chapter 6 Arjuna asks Krishna what would happen to a person who has full faith in Karma yoga but is unable to control his mind and senses and cannot practice it to perfection and passes away midway. Gita Chapter 6.Verse 37-38. Listening to the queries of Arjuna, Krishna answers that a person who has stepped into the path of Karma Yoga will never come to grieve in this world or in the next. Evil never befalls one who does good deeds. After death, he will be born in a family of prosperous and pious parents after enjoying the celestial world. Gita-Chapter 6. Verse 41-42.
But now in the modern society we foolishly do not consider the Guna and Karma but we look into the family background which has become the deciding factor. A son of a Brahmin is a Brahmin even though he is rude or rouge and fall to his feet and a son of a Sudra is considered an outcaste even if he has a profound knowledge and behaves a disciplined gentleman he is looked down upon……this is the irony of the civilised society……….What say????