This section is from the book "Understanding Astrology", by Ezequiel Gonzalez. See also Joanna Martine Woolfolk - The Only Astrology Book You'll Ever Need.
To read or interpret a Sun in House in Sign follow this method.
(1) Make three lists of the relevant keywords for planet, sign and house:
Sun
Basic Character, Identity
1st House
Public Image Personality collective leaders
Sagittarius
Expansively, freely, wisely
Optimistically, wide rangingly
The use the following formula to combine these keywords into a rational interpretation:
The [planet keywords] is expressed [signs keywords] through the [house keywords].
For example Sun in Sagittarius in the 1st house would become:
The [Basic character] is expressed [optimistically, freely and wide rangingly] through the [personality and public image].
This could means that the native is a very jovial persons that expresses himself happily and without inhibitions.
The same procedure is used to interpret any other planet in sign in house position.
How to interpret aspects:
To interpret aspects simply imagine planet "a" as a person being influenced by planet "b": according to the aspect that bind them together. For example if there is a square between the Sun and Mars, then the energetic self assertive actions of Mars would cause problems to the Sun. As the Sun represents the basic spontaneous character we may conclude that when the person acts energetically and harshly he is not able to express himself effectively.
Each sign has a combination of Qualities and Elements as follows:
Sign Quality Element Aries Cardinal Fire Taurus Fixed Earth Gemini Mutable Air Cancer Cardinal Water Leo Fixed Fire Virgo Mutable Earth Libra Cardinal Air Scorpio Fixed Water Sagittarius Mutable Fire Capricorn Cardinal Earth Aquarius Fixed Air Pisces Mutable WaterThe planets will be distributed in various signs throughout the chart. To determine the Sign signature you count the planets located in each quality (cardinal, fixed and mutable) and each element (fire, earth, air and water). There are then planets (sun and Moon included). Thus you single out the quality and element where you found the most planets. Then you look into the previous list to see to what sign this combination of quality and element correspond: this sign would be the sign signature of the chart.
For example, if the Sun is in Aries but there are 6 planets in water signs and 5 planets in mutable signs, then the sign signature would be mutable water; or Pisces. Thus, while the native would have an Aries character, he would also express some very Piscean attributes.
The Jones patterns (or any other planetary configuration that combines the energies of various planets into a unified pattern) are extremely important in any chart interpretation. The planets are the actual drives that energize the entire chart. Thus, when several of those drives are working together the pattern they form will be the dominant factor in the chart. When there is a strong planetary pattern present in the chart it should be interpreted first, and then the rest of the details in the chart (Sun position, Moon position, houses, etc.) should be interpreted in reference to the planetary pattern.
However, before going to far, you must check the expected effect of the planetary pattern against the background of the native's life history. Have he reacted positively to this pattern or not? Does he lives in harmony or dissonance with the cosmic drives?What level of cosmic sensitivity does he manifest? Once you establish this basic reference point then you can develop an accurate chart interpretation: You would be starting from a solid reference point; that is, the main astrological pattern and the native's reaction to it. The rest of the chart will expand on this.
The Houses represent areas of our worldly life; the signs represent personal attitudes while the planets represent inner psychological drives. Any one of them can be use as the fundamental element in chart interpretation. For example you may start with the Sun and analyze it in detail (Sign, house position and aspects) then do the Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Likewise with the Signs; you may start with a given sign and go around the zodiac analyzing each house and planet as they come along. However the most practical approach is to use the houses as our guide to chart interpretation. The houses represent worldly matters, the most tangible things in the Horoscope. Thus, it is easier to see what the houses mean in terms of social and physical affairs.
The primary goals of a Horoscope reading is to apply the wisdom of the chart to the everyday life of the native. Thus the houses as the more physical of all the horoscope elements are the ideal means to do so. In chart interpretation first comes the overview. Then the Sun, Moon and Ascendant, and finally the detailed House by House analyses. For each house we determine:
(1) The sign where the House start
(2) How many degree of that sign there are in the house.
(3) How many degrees of any other sign are there
(4) What planets are located in the house, and
(5) Any other sensitive point within the house
The sign where the house starts would determine the basic attitude of the individual toward the affairs of that particular house. For example, the 2nd house in the US chart starts in Capricorn. Thus the basic attitude of the United States toward physical possessions would be ambitious and prudent. If the house extends into another sign that sign also affects the affairs of the house. In the case of the United States chart the 2nd house covers 37.8167 degrees; of those, 17.8167 are in the sign of Capricorn and 20 degrees are in the sign of Aquarius. Obviously, with 20 degrees in Aquarius, this sign must also influence the affairs of the 2nd house. And so it is. However, this effect is secondary to the effect of the sign where the house started. Thus, in the case of the US chart the attitude toward physical possessions will continue to be basically Capricorn, but with an Aquarian undertone. Aquarius main characteristic is detachment and lack of emotional expression.
The planets within the house should be interpreted like we did with the Sun; that is using the formula:
The [planet keyword] is expressed [sign keywords] through the [house keywords].
 
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