Jyotish is a brahminical science and belongs to the Brahmin varna. According to the Vedas there are four varnas, these varnas are based on guna and karma. The four varnas are brahmins (priests, teachers, scholars), kshatriyas (kings, rulers, warriors), vaishyas (merchants,farmers) and shudras (artisans, labourers, servants).
This caste system is different to the caste system of classifying types of members in society based on one's bloodline and lineage. There is also another group not mentioned in the varna categories, i.e. mlecchas/untouchables, These are persons who do not conform to any of the four castes i.e. brahmins, kshatriyas, vaishyas, shudras and who stand outside of society. These outcastes could belong to a particular varna however, a lowly wandering beggar might belong to the shudra or brahma varna, a business minded criminal to the vaishya varna, a rebellious hero like Robin Hood to the kshatriya varna or an eccentric mystic hermit to the brahma varna. All castes in more evolved times could be classed as having brahminical qualities because everyone would be spiritually awakened and possessing knowledge.
By following one's varna (inherent potential,karma and dharma) all beings can move towards enlightenment in a harmonious manner, in agreement with divine will, thus moving harmoniously in the world/society, performing the most appropriate service.
This is illustrated in a short verse from the RigVeda talking on the human spirit Purusha:-
"The Brahmin was his mouth,
Of both his arms was the (Kshatriya)made
His thighs became the Vaishya
From his feet the Shudra was produced.."
In the same way a human cannot function well without all its body parts in good working order,this varna-ashrama-dharma model where each person adheres righteously to their appropriate varna ,enables human civilization to function healthily.
Varna means different shades and textures and is derived from the three gunas, or three primary attributes of nature sattwa (mode of goodness), rajas (mode of passion) and tamas (mode of darkness/ignorance).
Brahmins being mostly sattwic in temperament, able to perform purity in mind and habits, acquire divine knowledge and wisdom which they can impart to others. The Vaishyas are the trading and business class and are a mix of rajas and tamas. They deal with wealth and how to maintain its flow, sustenance and prosperity. The Kshatriyas are mostly rajasic, possessing a fighting, passionate spirit used to protect dharma (brahmins knowledge) and the people. They are the rulers, kings, politicians, upholders of the law, military, police. The Shudras are a mix of tamas and rajas, and are the working class people, labourers or the artisans. They are the foundation of society providing what is needed at the ground, base level.
People are a combination of gunas and can operate in two or more different varnas with one usually more predominant than the other.In today's society, A BRAHMIN Kshatriya for instance might be an ayurvedic doctor, who spends alot of time upholding or protecting that knowledge by being the head of an organization for that purpose.A BRAHMIN Vaishya might be an astrologer who sells alot of astrology books and related products or who operates alot in the media so that the knowledge of astrology is flowing prosperously through the society. A SHUDRA Brahmin might be a craftsman who produces gemstone jewellery for healing purposes.
There are numerous varieties and combinations in which these gunas and varnas blend together giving rise to the different types of people in our society.
The harmony of the Varna structure has gotten a little muddled because we are living in the dark age of Kali Yuga. According to the Vedic concept of timing, cycles on the planet rotate in four yugas, Satya yuga, 1,7280000 human years, treta-yuga 1, 296000 human years, dvapara-yuga 864,000 human years and kali yuga 432,000 human years. We have only passed 5,000 years or so in the Kali yuga phase so we are still only at the beginning.From a microcosmic view,there is a consensus that we run smaller cycles of these ages within the larger cycle and that a miniature satya yuga phase begins when sun harmonizes with the galactic centre in 2012.
Satya yuga is called the golden age, the age which is charactized by virtue, wisdom, religion, without vice or ignorance. Because of this emphasis on purity, the societal structure works in peaceful harmony. There are no hiccups . In treta yuga the good qualities in humans are reduced by one third. In dvapara-yuga, the good qualities are reduced by half, until we get to kali yuga, where only one fourth of human goodness remains and gradually reduces to nil as the age progresses.
Right now in Kali yuga,ignorance, hypocrisy and conflict reign supreme and much confusion abounds especially in the societal structure. The varna order is turned upside down. Because of this upside down turn, shudras and vaishyas end up playing the role of rulers, brahmins and kshatriyas are reduced to shudras, vaishyas impersonate brahmins for profit.
"O Pandava, the Brahmanas (Brahmins) and Kshatriyas and Vaisyas and Sudras, (in the Kali age) will practise morality and virtue deceitfully and men in general will deceive their fellows by spreading the net of virtue. And men with false reputation of learning will, by their acts, cause Truth to be contracted and concealed. And in consequence of the shortness of their lives, they will not be able to acquire much knowledge. And in consequence of the littleness of their knowledge, they will have no wisdom. And for this, covetousness and avarice will overwhelm them all. And wedded to avarice and wrath and ignorance and lust, men will entertain animosities towards one another, desiring to take one another’s lives." (Vaisampayana)
"No one follows the duties of one's own caste, and the four Ashrams or stages of life also disappear. Every man and woman takes delight in revolting against the Vedas. The Brahmans sell the Vedas; the kings bleed their subjects; no one respects the injunctions of the Vedas. The right course for every individual is that which one takes a fancy to; a man of erudition is he who plays the braggart. Whoever launches spurious undertakings and is given over to hypocrisy, him does everyone call a saint. He alone is clever who robs another of his wealth; he who puts up false appearances is an ardent follower of established usage. He who is given to lying and is clever at joking is spoken of as a man of parts in the Kali age. He alone who is a reprobate and has abandoned the path of the Vedas is a man of wisdom and dispassion in the Kali age. He alone who has grown big nails and long locks of matted hair is a renowned ascetic in the Kali age. (The Tulasi Ramayana)
For those practising brahminical professions, it is useful to know what is expected of a brahmin. The essence of the brahmin is that they receive the divine knowledge which can be imparted to others especially those in charge, and the rest of society will follow under that divine guidance. But in order for a brahmin to access that knowledge one has to live according to a certain level of purity, especially purity of the heart and mind, but also the body. Once upon a time brahmins, which includes astrologers were taken care of by the ruling classes and served as their counsel. In today's age, we find brahmins having to resort to all kinds of means just to survive, whilst being tied to lifestyles in society which are anti purifying. As a result, it becomes difficult to maintain the internal detachment, humility and purity required to access the higher knowledge, the real vidya. Real knowledge, internal vidya becomes deficient.
The Brahmin is supposed to be chaste in mind and body, so he can have power to perform mantra. He is in charge of sonic magic (mantras), to help stabilize the world around him, acting as the conduit of divine wisdom. A brahmin is not supposed to amass wealth and must live only according to his basic needs. He is supposed to be free of indulgence and a master of penance. The brahmin's duty is the ultimate sacrificing role. Other castes do not have to follow such strict standards.
"A Brahmin is one who lives and moves in Brahman. He remains above the pair of opposites. He is unmoved in joy and sorrow, pain and pleasure, pride and prejudice, has conquered desires and is free from ego-sense. The one so equipped is indeed a Brahmin." (Vajra Suchikopanishad)
Kaliyuga is a time of confusion and whether we can fully live up to ideals as brahmins or kshatriyas or the other two varnas is highly questionable. But nothing in the universe is just for the purpose of doom and gloom, there is an eternal blessing which runs through everything.Kaliyuga says we can make leaps and bounds in our transcendantal awareness through just a few steps of sincerity, faith and little bit of effort.
Reaching God in the Satya, Treta and Dvapara Yugas was difficult. One had to go through many trials and penance before one could reach God in those ages.There are different standards and methods set in different yugas in order to connect to the divine. But in the Kali Yuga, the present age, reaching God is very easy as long as one meditates on the divine name constantly. Those who meditate on the divine name can experience the reality of God . It is in fact THE important dharma that Krishna prescribes for this time.