A friend of mine who's an engineer with a pretty reason-based mindset is starting to dabble into the occult. He asked me for a Rune reading and liked it very much, so he opened up to the possibility of getting an Astrological reading as well. Yesterday he asked me why, when he looked to the actual position of the Sun at the time of his birth, it was in Aries rather than Taurus, his astrological sign. Since I'm not yet very familiar with Astronomy, I had to research a bit to get to the reason and found an article that explains it very well. Essentially, the precession of the equinoxes, which is determined by Earth's tilt, changes the way we observe the apparent position of celestial bodies in relation to the constellations; aside from that, each constellation has a different apparent length and there's a thirteenth constellation called Ophiuchus. Although Astrology uses astronomical data for its calculations, it doesn't take into account any of those things and obeys basically the same rules set into place by the ancient civilizations who first used it. On top of that, as far as we know these civilizations had no knowledge of the existence of Uranus, Neptune or Pluto as well as countless other bodies that are part of regular astrological studies now.
So how can we trust astrological connections and interpretations if they're not based on sound astronomical data? The same way we can trust science as a whole or any other discipline: we take the information as a reference point and work on that. Note that I used the word "apparent" above because all we have from an astronomical perspective is a series of calculations based on our current observational capacity; these measurements don't take into account the fact that constellations are just imaginary figures that our ancestors drew using the stars they beheld as dots; these stars aren't even in the same vicinity of the galaxy, many may have been long dead when they surveyed them, some may not be stars at all, not to mention how gravitational lensing and the recently confirmed, spacetime-warping gravitational waves could've affected the readings. Additionally, the constellations also receive their name and meaning from myths and legends, there's no verifiable scientific reason for their existence and importance, but they're useful descriptors and so Astronomy uses them, Astrology just goes deeper into them.
Everything we can see, hear or feel in this material universe is a perception. When we study history, for instance, we only get what has been recorded by one or more people, each of them using the resources available to them. In most cases, historical accounts are produced by individuals who didn't live through the experiences they describe and, even if they did, their vision responds to their personal biases and opinions as well as the conditions of their particular social, political, economic or psychological context; they couldn't see things from anyone's position but their own and even if they were exceedingly careful and as impartial as possible, they couldn't have obtained the myriad details observed by everyone involved in any particular situation. That means that our view of past events is heavily slanted, incomplete and often deliberately doctored. Mind you, this is the science upon which pretty much all of our knowledge about the world is based, without it we wouldn't have any concept of the progress of knowledge throughout human existence.
What about Mathematics? It's our most precise and profound tool for describing and understanding the Universe and yet, it depends on self-defined concepts such as numbers and operators, which were arbitrary back when they were created and had to change over time. For most of our recorded history the number Zero (0) didn't even exist, people counted without it, some using blank spaces or other symbol to represent the idea. Recently, due to my decision to study this subject again, I came into contact with the Mathematical Multiverse, which is the collection of interpretations of universal rules as described by various mathematicians who established their own paradigms for understanding the principles of existence, seeking the most harmonious and all-encompassing images. Each of these mathematical universes has had its time in the spotlight and then drifted into obscurity as a new, nicer model emerged, meaning that the vast majority of human beings never learn about previous interpretations.
Physics and Chemistry both evolved from ancient occult practices conjoined with Philosophy and various stages of mathematical studies. Their current precision has a relatively recent historical background and many of their tenets are a work in progress; for example, the Standard Model of Particle Physics is so far the most accepted approach to comprehend the forces and phenomena of our Universe, but it doesn't include gravity and can't describe many known behaviors of bodies in the cosmos. These limitations and drawbacks exist also in Biology, Psychology, Geography and all other scientific pursuits.
In conclusion, no science is final or truly factual, all of them are tools just like so-called "pseudosciences" like Astrology and Alchemy. They help us delve into the world and ourselves, but they can't actually give us any definitive answers and that's excellent, because it's in the questions that evolution lies. I approach all knowledge from as open a perspective as I can, every bit of information (even if false or manipulated) provides an insight into the state of our reality. All forms of study are constantly changing and our understanding transforms with them. Ultimately, each individual or group lives in their own version of the world which may or may not subscribe to the general perspectives. Every practice and discipline is a potential path toward deeper truths and no single path is perfect, no single tool is total. All things have their own value if they're taken in their own place and time.