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Introduction to Casting Lots

So, what are the Lots in astrology? The Lots are part of an ancient Hellenistic technique known as "casting Lots," which combines 3 points in a horoscope (a chart, not always a birth chart) to find where those energies, and the associated topics, converge.

The Lots themselves are symbolically significant calculated points. These points are typically calculated from the distance between two planets which is then projected from the degree of the ascendant.

Why do we care? The Lots are able to show more specific things in a chart that may not otherwise have a clear rulership.

History of the Lots

The Lots are Hellenistic in origin despite also being known as Arabic Parts. The origin of the Lots are attributed to the mythical figure, Hermes, in a lost text known as the Panaretos. Since there are no surviving copies of the Panaretos, we only know it existed from other authors referencing it and its contents. It is estimated to have been written around the 1st century BCE or slightly earlier.

Its alleged author, Hermes, may have been an individual using the name, a group of people using 'Hermes' as a title for a master of something, or perhaps the trickster god himself. Among its contents, the Panaretos included calculations for seven planetary Lots. These Lots became known as the Hermetic Lots due to their author, Hermes.

From these original seven Hermetic Lots, astrologers began to reverse engineer the calculations to create new Lots. The Lots eventually spread to the Arabic astrologers who developed the technique further and created many of their own Lots. Within the Arabic tradition, the Lots were called Parts due to slight differences in phrasing from translation. This is why the Lots are also known as the Arabic Parts.

Purpose of the Lots

The Lots were used to find where a specific topic exists in a horoscope. Life is complicated. It can't be easily divided between 12 houses and 7 planets. The Lots allow us to fill in the blanks and find specific topics that may have multiple possible significators.

For example, most astrologers associate both the sun and Saturn with the father. In that case which one are you supposed to look at? Are you supposed to use both? Do you just use the one that fits better? What about the 4th house for father? It gets complicated pretty quickly.

However, using the Lot of the father eliminates that problem. Calculated from the degree of the sun to the degree of Saturn, then projected from the ascendant by day (reverse Saturn and the sun for night births). With this calculation we're able to combine the topics of the sun and topics of Saturn to find where the specific topic of father is found in a chart.

The Lots can be used in natal astrology, electional (picking times to start things), mundane (world events), and horary (asking specific questions). They're the foundation of the technique, zodiacal releasing. They can also used in profections, solar returns, and transits.

Calculating Lots

As you can probably guess, this involves math. Don't worry, I'll show you the easy way. I don't like math either. First let's talk about the structure of the formulas though, so you understand what we're going to be making a calculator do.

Every Lot formula you see will be:

1. Take the distance between point A and point B

2. Project that distance from point C

3. Not always, but usually, reverse point A and point B for night charts.

A "night chart" means any horoscope (doesn't have to be a birth chart) where the sun is below the horizon. This is easy to check if you understand that a horoscope is a diagram of the sky.

The AC is the eastern horizon where the sun rises, the MC is around noon where the sun culminates, the DC is the western horizon where the sun sets, and the IC is where the sun is below the earth around midnight. So, if the sun is on the MC side of the AC/DC axis then it's a day chart, if the sun is on the IC side of the AC/DC axis then it's a night chart.

Point A and Point B are usually going to be a planet or another Lot. When you're calculating the distance between the two points, you start at point A and count around the wheel in zodiacal order until you get to point B.

The easiest way to do this manually is to take advantage of each sign being 30° and basically just work out the differences.

Here's an easy manual calculation example using the Lot of Fortune. The Lot of Fortune is found by taking the degree of the sun, to the degree of the moon, then projecting that from the ascendant (reverse for night charts).

1. The sun is above the horizon so we use the day formula

2. Point A is the sun, Point B is the moon.

Since they're exactly opposite we already know it's 180°. However, you could also start from the sun and add 20° to get to the end of the sign. Then you would count the whole signs between the sign of the sun, and the sign of the moon (shown in red). There are 5 signs, so we multiply 30° per sign, by 5 signs, for a total of 150°. Now, let's add that 150° to the 20° we started with for a total of 170°. All that's left is to add the last 10° for the sign the moon is in for a total of 180°.

You can also start with the sun, add 20° to get to the end of the sign, then add 10° for the sign the moon is in. Take that 30°, basically the change left over between the whole signs, and project it from the ascendant. That moves the ascendant to 15° of the next sign. Then you just slide it forward one sign for each of the whole signs we counted between the sun and the moon, 5 signs.

The Easy Way to Calculate Lots

Assuming that, like myself, you don't have access to professional astrological software, you're going to need some free ways to do this online.

The first thing you need to know about using calculators for Lots is that while the formulas make more sense to humans in the format we already covered, things get switched around a bit for machines.

Lot format for humans: Point A to Point B, projected from Point C

ends up becoming

Lot format for machines: Point C + Point B - Point A

Now let's look at our options for calculators!

Astro-Seek's Arabic Part Calculator


· Allows you to set up the calculation manually so you can use whatever formulas you prefer


· Having to re-enter the birth data every time

· Having to manually enter the formula

· Only being able to calculate one Lot at a time

Astrodienst Options

Once you go to and go to "extended chart selection," we have a couple options for "chart drawing style" to calculate Lots.

However, unlike astro-seek, we don't get to choose which formulas it uses. Some of the Lots that will be generated use formulas that I consider to be incorrect, so be careful which chart drawing style you use and which Lots you're looking at.

1. Hellenistic Chart Drawing Style


· All the Lots generated use formulas I consider to be correct

· This is the easiest way to get the correct calculation for the Lot of Eros


· Only calculates Fortune, Spirit, and Eros

2. Arabic Points/Al-biruni Chart Drawing Style


· Generates a chart with all 7 Hermetic Lots

· Clicking PDF, Additional Tables gives you a list of 89 other calculated Lots


· I consider the calculations used for the Lot of Necessity and the Lot of Eros to be incorrect

· The 89 other Lots all use Al-biruni's calculations, not all of them make sense

Calculating the Hermetic Lots

Until I have several hundreds of dollars laying around for pro software or until one of y'all designs a better Lot calculator, this is my process for calculating the Hermetic Lots.

1. Astrodienst: Arabic Points/Al-biruni - this has the most usable info so this is primary. I use it for Fortune, Spirit, Courage, Victory, and Nemesis.

2. Astrodienst: Hellenistic - I basically just check this for the Lot of Eros, write it down, then close it.

3. Astro-Seek's Arabic Part Calculator - Since everything is manual, I only use this for the Lot of Necessity, which is found from Mercury to the Lot of Fortune, projected from the ascendant, by day (reverse at night).

Using the Lot formula format for machines:

Lot of Necessity (day): Asc + Lot of Fortune - Mercury

Lot of Necessity (night): Asc + Mercury - Lot of Fortune

Critical Thinking & Discernment

There are hundreds of Lot formulas that are floating around on the internet, in ancient books, in mistranslated works, etc. Don't just take something you read about the Lots as truth.

Part of what I hope to do with my continued work in this area is to research and test these Lot formulas to make sure they make symbolic sense and actually work in practice. To that end, I plan to create a comprehensive reference so people know which formulas to use, which Lots do what, and who said so.

Until then, you can subscribe to my mailing list to get important, yet infrequent, updates on my work. You can book a consultation with me to talk specifically about your Lots.

You can also purchase the recording from a webinar I gave for Fresh Voices in Astrology on the Hermetic Lots. In the lecture I cover what the Lots are, where they came from, how to calculate them, how to interpret them, what each of the 7 Hermetic Lots mean, examples of all 7 Hermetic Lots, and the symbolic reasoning behind the Lot formulas. There's tons of info so check it out!

The next blog post (at some point) will cover general interpretive rules for Lots and understanding the symbolic reasoning behind the formulas.


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