Predictive Tools in Astrology

If you look at all the predictive options offered at a free chart site, you’ll get a long list. This reflects the experimental nature of much astrological investigation by symbolic thinkers operating in consumerist societies that love choices — no matter what they are.

These are not all of equal value or legitimacy. I will be addressing only those marked with a blue dot.

These are not all of equal value or legitimacy. I will be addressing only those marked with a blue dot.

More and more laypersons are becoming familiar with these terms and charts. So I am going to explain each tool and tell you if I use it and why.

Let’s take a look at the natural phenomenon behind the various tools of predictive astrology, and they metaphors they use and how they are applied. Not all of them have as solid a basis as you might assume, nor is there always agreement on how they should be calculated.


There is no real disagreement on what transits are or on how they are tracked. However, there may be tiny incremental disagreement in exact planet positions between different programs that use slightly different predictive algorithms to track the planets. This amounts to minutes of arc, not degrees.

These are simply the current movements of planets in the sky seen against the backdrop of your birth chart. I use them.

Venus transits the Sun in 2012. Image from NASA.

Venus transits the Sun in 2012. Image from NASA.

I not only follow the transits through the flat wheel chart (longitudes), but the declinations as well. They are just as important. Sometimes this means twice as much information or more for any one person at any given time.

The transit of the Sun each year to its original position in the birth chart is called a solar return. The monthly transit of the Moon to its original position in the birth chart is called the lunar return.

I don’t cast (or interpret) charts specifically for the exact moment of a solar or lunar return. (Same for Venus or Jupiter returns.) These are very brief transits, which cannot in my view be used as reliable guides for creating a whole new set of houses for a predictive scheme for a year (solar) or a month (lunar). The solar return is at most a transit of a few days duration, the lunar return a few hours. By attempting to rely on such charts for predictive purposes a two-layer overlay is created over the birth chart that confuses and obscures a clear view into it and of other, more complete predictive tools.

Note: The only houses that truly matter are the ones defined by your birth chart. All prediction must use this backdrop to keep tight relationships with the natal chart. Adding into our thought processes houses as defined by a solar or lunar return creates contradiction, confusion, and well lunacy.

Secondary Progressions

I’ve actually seen astrologers and students say they don’t know where the day-for-a-year principle came from. It is a geocentric metaphor: one rotation of the Earth around its axis equated with one orbit of the Earth around the sun, our system’s axis. That is the natural phenomenon that forms the basis for the day-for-a-year metaphor.


This is an internally consistent and cohesive metaphor taken straight from nature, which not only makes sense, but asks that the progression method follow nature by simply tracking original planetary movement and projecting this forward in the day-for-a-year application of progression.

I use secondary progressions as my second predictive tool. Again, I track the progressions in declinations in addition to longitudes (flat wheel chart).

However, I use them with a qualification, because the modern common method for calculating these progressions does not progress the Ascendant and calculated points as they actually moved in those first days of your life. In other words, the metaphoric principle is there, but it is as if we are pretending the Earth did not rotate as we know it does, with astrologers substituting an incremental movement towards annual net gain of these points. This means that what is commonly calculated as your progressed Ascendant isn’t — it is made up purely for the convenience of astrologers. I have requested that David Cochrane include an option for true progressions that follow the Ascendant’s progression through the zodiac for each year of your life just as it moves each day of our lives.

Solar Arcs

This method is similar, also using a day-for-a-year metaphor, but all planets and other points (Asc and cusps) are moved as if they were the sun. This means only one factor in a solar arc chart is based on any natural phenomenon that occurs. That is what I call symbolic fiction.

I don’t use them. Instead, I dig deeper into the numerous minor aspects that can be found frequently activated in the secondary progressed chart. When they culminate, especially accompanied by others, they are not ‘minor’ at that moment, but important influences significant to timing. I have studied this in-depth and have found validity in all previously ignored 15-degree aspects when at or near culmination, including 15, 75, 105, and 165°. (These can all be referred to as “quindeciles.”)

Primary Directions

Primary directing is the oldest method of progressing a birth chart, apparently predating Ptolemy by a century since it is first mentioned by Dorotheus of Sidon in the third book Carmen Astrologicum. Its premise is a perfectly sensible one. It posits that there should be significance to the arc gaps between say a rising planet and the Midheaven; Mars just above your Ascendant will continue rising as the globe rotates and will eventually make it after some hours to the mundane Midheaven for that location, and to the Midheaven as marked in the birth chart. That should be a significant timing factor of Mars reaching culmination in mundo (as the globe turns).

However, one degree of rotation is arbitrarily equated to one year of life in progression. Why?

A day is defined as a single turn of Earth on its axis. With primary directions ‘day’ is equated with a single degree’s turning of Earth. This redefines ‘day’ using a rough approximation of solar movement in a day, mixing the metaphor.

Here are the different ways that primary progressions have been reasoned:

  • Ptolemy: 1° = 1 year of life
  • Naibod: 1° = 1.0146 years of life (360° circle divided by 365.2422 days)
  • Cardan: 360° / 365 = 1.0135 (Naibod and Caran were applying Right Ascension to their notion of culminating measures)
  • Kolev uses length of Mean Lunar Year: 1° = 0.9844 years of life
  • Kepler and Placidus interject other considerations

“Maybe its as simple as one degree equals one year of life, but there are some reasons to think its more complicated than that.”
– David Cochrane

In addition, if the natal chart is off even just a little, such primary directions become enormously inaccurate in their predictive timing. Many birth charts are off by a few degrees on the Asc. Subsequent primary directions will be off by the equivalent number of years.

I don’t use primary directions. They were dropped for good reasons. They amount to more symbolic fiction. They are a confused mess of theory, a mixed metaphor, an arbitrary notion with no agreement on execution.

Tertiary Progressions

This method moves everything at the rate of the Moon’s movement, but there are actually two methods which don’t agree. More symbolic fiction. I don’t use them.

The So-called Progressed Composite

Midpoints between two charts are used to create another single chart for a partnership called a composite. Perfectly reasonable so long as it is not seen as more important than the two natal charts that compose it.

However, an arbitrary rate of movement is applied singly to all planets, or some average or mean movement is applied to each in an attempt at progression. This means it isn’t based on any remaining thread of reality. There’s no such thing as a “progressed” composite since there is no singular set of original naturally occurring planetary positions with continued movement to set the rate of progression. Another symbolic fiction.

Transits to the composite chart are perfectly fine for tracking trends of astrological weather for a partnership IF the declinations are included. If not, there will certainly be a gap in the composite interpretation from the beginning and probably in transit tracking as well. It is also important to know you are first working with two accurate birth charts to create an accurate composite. Otherwise your timing of transits to the main axes of that chart will be off by weeks to years.


There are more predictive tools, but we get deeper and deeper into symbolic fiction. So there is no use is going over them.

My requirements for a predictive tool is that it must follow nature’s original orchestration in the sky as closely as possible, and that it must be based on a clear, unmixed cohesive metaphor that is not altered in execution. Natural phenomena are the energetic reality basis for the coordinated metaphors of astrology. We don’t get to make it up for symbolism’s sake and still seriously believe we can rely on this ancient respected science for making life decisions.

Astrology is a language and its metaphors need to be clear. Otherwise you get the confusion that comes from truly bad cosmic grammar. Not every tool that has been invented by astrologers is reliable as a predictive tool, even if it makes sense — and even if astrologers see some supportive correlations.

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3 thoughts on “Predictive Tools in Astrology

  1. I really liked this post. And I appreciate your detailed explanations. Although I am not an experienced astrologer in years of practice, I have felt intuitively that secondary progressions make sense and have significant value. And that minor aspects are not minor. Thank you for validating that.

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