On the subject of Astrology

I was chatting with a friend who is currently studying an advanced level of Astrology.

She explained that, unlike the standard newspaper horoscope stuff, the Astrology she was studying was far more specific to each individual.

I asked, "yes, but isn't any reference to the stars, or planets still making victims of people to those influences?". Whereupon she replied, "no, they're influences, they don't dictate what we do", or words to that effect.

Now, in my work I explain how we're all subject to external influences which guide, but don't dictate our behaviours. A simple example: standing or working outside in the sun, for hours or days, with no protective clothing, or protective lotions. We'll end up severely burned, and if we stay in the sun, ultimately, dead. The physical system (in this case, sunlight) constrains our bahaviours. In technical terms, it's called "downward causation" - the (bigger) higher-order system constrains the lower-order parts (people).

Okay, so why not also the planets and stars forming a "downward causative" influence that guides but down not dictate what we do as we go about our day?

Fair question.

From a basic scientific, rational basis, the distant stars and planets have negligible physical influence on our bodies -- unlike our local sun, and the prospect of being sunburnt. We're not going to get sunburnt by sitting under a night-sky, filled with a countless stars, galaxies and whatever. So we can rule out (distant) physical influences as being instrumental in determining our behaviours, personalities, etc.

So what's really going on?