"Correct?" Planetary Rulership

I had a very good question from a student about how to deal with differences in list of planetary rulerships.

What do you do when Agrippa says one thing Al-biruni another and Lilly a third thing about which planet rules something?

First, we are in the grip of the modern world view which wants to take a strictly formal logic view of everything. A=A, A is not B, therefore A = B is false. So we want to have strict categories and fit everything into the one "right" category. But reality is more complex than this. While hate is diametrically opposed to love, we have all had the experience of hating and loving someone at the same time. A is not B, but B = A!

This is the baggage we bring to the question of what planet rules a particular thing. But let's step back a bit and see what we are doing when we discuss planetary rulership. In fact all material things contain all 7 planets in varying amounts. "Also, amongst vegetables, every thing that bears fruit is from Jupiter, and every thing that bears flowers is from Venus; all seed and bark is from Mercury, and all roots from Saturn, and all wood from Mars, and leaves from the Moon." Agrippa Three Books of Occult Philosophy Bk I ch 30.

So when we say that a particular thing is ruled by a planet, we are making a judgment about which quality or qualities we think predominate in the thing and then a further judgment about which planet is associated with that quality. Generally we would say that roses are ruled by Venus, because of their beauty and sweet smell, but if I get pricked I may suddenly focus on Mars who rules their thorns.

The key with planetary rulership attributions is not to determine the one "right" classification, but to get a sense of what quality the maker of the list was focused on and why. In a very real sense by learning about the things a planet rules, we are learning about the personality of the spirit of the planet, just as if I know a person likes coffee houses, jazz and wearing a beret, I'm learning about their personality.