Whereas Sun emits energy, Mercury instills this energy to neurons for the development of brain cells. If Sun is freedom of self, sense of ego and generous traits, Mercury is consciousness, sanctity of existence, sober and wit, wise and wisdom. The conjunction of both Sun and Mercury constitutes a famous, proverbial, philanthropic, prowess and praiseworthy association what is called Budha-Aditya Yoga, an asset of the horoscope under which a native is born. It is synonymous to Bhadra Yoga, (one of Pancha-Mahapurusha yogas) that has been energised.
The legitimacy of this yoga is when it gets extra strength from the sign of own, exaltation or friends such as Aries, Gemini, Cancer, Leo, Virgo, and Saggitarius. Then, it uplifts the life of the native with certainity. If the yoga germinates in sign of debilitation such as Libra or Pisces or it is ruined by the association or aspect of malefics such as Mars, Saturn, Rahu or Ketu, its natural strength is pitiful. It is a general rule of astrology that the Sun is exalted in Aries and debilitated in Libra. Similarly, Mercury is exalted in Virgo and debilitated in Pisces. Therefore, this is apprehensible how Sun-Mercury in Libra, Capricorn and Pisces will enmoure the native what they do in Aries, Gemini, Leo, and Virgo.
Kalyan Verma in Saravali, Baidyanath in Jataka Parijat and Prithuyasas in Horasar give detailed description of this conjunction. All the learned ancient astrologers consider it as a pious, sensible, humorous, instinctive and benevolent yoga in almost all houses of horoscope. Although the houses 6th, 8th and 12th are the places of atrocities, yet if the conjunction Sun-Mercury is disposed in the sign of own or exaltation, the enigma of malefic places is reduced. For an illustration, see Saravali, Chapter 31
If this yoga appears in the ascendant, the native is erudite, talkative, stout body, bold, intelligent and long lived.
The best example of this dictum is the chart of Abrahm Lincoln where Sun-Mercury occupies ascendant and is free from all the malefics. He was a son of poor and illiterate father who could not serve any help to his son. Even then, Abrahm was inspired by inherent energy of harmonious disposition of strong ascendant, Sun-Mercury conjunction and aspect of divine Jupiter on ascendant lord Saturn. As a result his mind was equipped with active, sensible, endurent and humourous brain cells. He studied in the light of lamp posts on road. His dream was to reshape his country with hunkey-dory and bonhomie. One day he sworn in as the president of most powerful country America.
If it is in 4th, (8th or 10th) house, the native is fond of poems(literature), famous, wealthy and has king like qualities. His body may be heavy with unsymmetrical nose.
The yoga in other houses make the native virtuous. However, it is not believed good in 7th house because such a native is sexually weak and may get jail sentence for his unsocial mis-deeds (the native may be a thief, smugler, fraudy, murderer or agonised dictator).
The good and bad aspects of this yoga disposited in 7th house and malafied by the proximity of Mars and aspect of Saturn, appear in the life of Adolf Hitler who started his carear as a house-painter. Mars-Saturn relation is pernicious and cause sudden calamity. Hitler was appointed Chancellor of Germany on 30th Jan. 1933. Earlier, he was a soldier of exorbitant valour and, therefore, was awarded the Iron Cross for bravery and distinguished military service. In 1923 he was arrested and confined to jail because he participated in the abortive Nationalist coup. After having consolidated power he embarked upon schemes to unite all the people of his country to revive Germany great, that lost her honour due to obnoxious shackles imposed on her by the Treaty of Versailles. Although he exceedingly loved his country, yet he could not get name and fame because of his agonised dictatorship and exodus of Yahudis.
The disposition of the Sun-Mercury in 10th house bestows the native name, fame and prosperity all over the word and he enjoys the life like a king provided the conjunction does not appear in debilitated sign.
It is observed that natives bestowed with Budha-Aditya yoga are bold, sincere, efficient, eloquent and erudite. They have an inharent source of energy which engross them to achieve the goals of their life. They have amazing endurance and hence never disheartened or degraded on failure. They augur what they want in their life.
Siri Mao Bhandarnaike, the first Prime Minister of Sri Lanka benedicted of this sacred yoga in the 9th house of her horoscope and in 5th house of the horoscope of Benito Mussolini . Smt Bhandarnaike is a name of repute but the name Mussolini is of hate, why? In the chart of Smt Bhandarnaike the yoga is free from any affliction and gets strengthened being arisen in Aries, the sign of exaltation of the Sun. She had ceremonied highest position three times in 1960-65, 1970 and 1994-2000.She has been known for her sobriety, sociability, and auspicious and gracious work to initiate the non-alliance countries to assemble on a common platform to put and solve their problems. She never dismayed in her social, political and family life even after when her husband was assassinated in 1959.
In Indian political realm we observe the vivid array of Sun-Mercury on our president Dr Abdul Kalam (Sun-Mercury-Ketu in Virgo in 10th house), prime minister PV Narsimha Rao (Sun-Mercury-Mars in Gemini in 10th house) and Dr. Man Mohan Singh (Sun-Mercury in Virgo in 10th house), election commissioner Shri T N Shesan (Sun-Mercury in Scorpio in 12th house) and film actor Amitabh Bachchan (Sun-Mercury-Mars-Venus in Virgo in 8th house). The yoga benedicted them compassion, compatibility, benevolence, philanthropy and unscrupulous venerable mental structure. They are proverbial in their high education, performing duties and achievements to occupy high position because they left no stone unturned in their respective fields.
If Sun-Mercury conjunction is affected by aspect or association of either Jupiter or Venus, the person gets spiritual evolution and gets augural traits. Such persons do not have any fear and do not evade from tremors of life because they have stable mind which engross to target of life. Mercury reflects the fifth Principle in us - Manas (eu). When mercury radiates positive rays of thinking and wisdom, the passion of Venus is sublimated completely and the brain is activated to focus the radiations to target. This is the highest position of men's mind (eu) when it gets rid of materialism and divert to get absolute calm and salvation.
If a person has weak mind, ie, weak Mercury, he should improve by taking meditation and some Ayurvedic medicines such as Brahmi and Shankhapushpi.