Q - What does Mercury signify?
A - Academic knowledge and degrees are the prerogative of Mercury, Vidya Mathula Karako Budha. Books, publishing, knowledge, mathematics, sculpture & arts all come under his domain. If he be exalted in one's horoscope, the native will become a great scholar. ( Example horoscope is that of Augustus Caesar who had exalted Mercury in Virgo ).
This science of the Heavens was called by the Germans as Cosmo-Biology. To them, Cosmo-Biology was the calculus of cosmic interrelatedness. It simply means the celestial influences on terrestrial affairs as per the principle " As Above, so below ".
The role of Mercury in Horoscopy
Mercury in the Ascendant
Mercury in the Ascendant makes one a scholar.Will be intelligent
and clever. Will be a master of arts. Will have good oratorial
prowess and can captivate people with speech. This position of
Mercury confers high longevity.