Basics

Some basics:

1st house-brain-Jupiter and mercury get Digbala here. Jupiter is for Intelligence or Dhi Shakti, Mercury is the "articulation" of the intelligence.

In Jaimini sutras, it is mentioned that Jupiter in trines to Svamsa(authorship, but may not be able to speak that fluently in an assembly), however, venus and mercury can give that ability, though authorship abilities are lesser for these two.

Moon gives a good imagination to create prose.

2nd house: Vak, speech, eyes, eye deformities can be seen in 2nd house, but eye sight itself is not seen from 2nd house. It is seen from the 10th house. This is because 10th house is 9th from 2nd house and thus protects the 2nd house.

3rd house: Ears, however it does not rule hearing. Hearing comes from 11th house.

4th house: Heart, Mind(not be confused with Buddhi). The 4th house is the storage of emotions. Moon ruling love and Shukra ruling passion get digbala here

5th house: Belly, stomach, all digestive acids are generated here. Thus the 5th house helps in "digesting" the knowledge.

The natural 5th house is Leo, and the Lord Sun is the biggest digestor. The fifth house thus rules the ability to "discriminate" or "digest" knowledge.

Regards
Partha
http://parthaastro.blogspot.com/

Fifth and 9th lords

Why are 5th and 9th houses considered houses of Lakshmi?

Lakshmi- Vedic numerology number as per katapayadi system is "5"

Simha Rasi is the fifth Rasi in zodiac. Who is the lord of Simha rasi? It is Sun who represents Atma.

Atma is nothing but the individuated form of Paramatma. Thus it represents the spiritual energy of the Lord. Fifth from Fifth, that is Dhanus represents the material energy of the Lord.
 Thus Both the Kona Sthanas of the Zodiac represent the Energy that permeates the Universe. This is different from the Consciousness, which is Vishnu.
Without energy, there is no matter, and without Matter there is no Material.