We want to clear up obtuse misconceptions about the 8-House Topical System. Before we do, we categorically reject and dismiss the 8-House System, and the decans due to the fact those are non-Greek Egyptian systems modified by Greek Egyptians.
In the Egyptian Old Kingdom right around the time of the 3rd or 4th Dynasty circa 2600 BCE, someone decided they needed to figure out how to tell time at night. After decades of watching the night skies using a water clock or hour-glass, they grouped the stars rising over the horizon into 36 star groups occupying 10° of the sky which you know as decans or faces.
Notwithstanding the fact that around 2100 BCE two different competing decan traditions evolved, the decans evolve into omen lore. Omen lore is not astrology and astrology is not omen lore. Sure, astrology originally began as omen lore but it evolved after more than a 1,000 years as mundane astrology (and natal astrology evolved out of that). The omen lore of the decans never evolved. Even worse, it devolved into magic. Or magik. And even magick. Whatever. What you end up with is this:

Yes, that is the original 8-House Topical System. The numbers are the corresponding houses in the 12-House Topical System. Where are the signs? Why would there be any signs? The Egyptians did not have a zodiac, at least not one comparable to the zodiac we know and love.
If you are familiar with Egyptian history, the question isn’t, “Who ruled Egypt?” rather the question is, “Who didn’t rule Egypt?” because the majority of the ruling dynasties were foreigners or people alien to Egypt. In the 7th Century BCE, there are ethnic Greek pharaohs for a brief period before the Nubians gain control. The Medo-Persian King Cyrus Christ conquers the Greek-speaking Canaanites known as Chaldeans (the “Neo-Babylonians” according to the incompetents in Academia) in 529 BCE, then conquers Egypt in 526 BCE deposing the Nubians and replacing them with Persians who introduce the zodiac to Egypt. Later, Alexander the Not-so-Great conquers Egypt ousting the Persians.
While the Dendera Zodiac was introduced to Egypt after the Persian conquest, there is a question of who introduced it but there is no question about the origin of the Dendera Zodiac. This gets complicated. Was it Persians or Greeks in Persia (either before or after the conquest by Alexander the Not-so-Great) who brought it to Egypt? Or was it Greeks who got it from the Assyrians or Kassites (the people the incompetents in Academia call “Middle Babylonians”) who made it happen?
The only thing that is certain is the Dendera Zodiac is of Sumerian origin:

We lifted that piece out of the zodiac so’s you could see it better. What you’re looking at is a raven standing on the back of a lion standing on the back of a serpent.
The image of the Lion, the Serpent and the Raven are undeniably, unmistakably, irrefutably, absolutely, positively, originally Sumerian in origin. Yes, it actually means something and you can find out what it means when we explain that in our musings on [Lions & Serpents & Ravens, oh, my!] which we haven’t put up yet. That means the Dendera Zodiac cannot possibly be Egyptian or Greek or Greek-Egyptian in origin.
Obviously at some point there is a marriage of decans with the zodiac. Part of the problem is that by the 1st Century BCE there are now more than a dozen different competing decan traditions which begs the question, “Which decan tradition was actually used?” We know Asclepius used decans and apparently so did Hermes but were they aware there were competing traditions and why did they use the tradition they chose? We don’t think those questions will ever be answered.
After crow-barring the decan system onto the zodiac, what you have is the 8-House System which is the first 8 houses of the chart. Contrary to popular belief, the chart was not divided into 8 houses. There is a conflict because in the 8-House System, the 4th House is death and the 8th House is life (according to Timaeus who seems to have been quoting Hermes).

Where’s the Midheaven Point? What Midheaven Point? They didn’t use it. Seriously, only a tiny fraction of charts using the 12-House System indicate the MC Point. At some point later (no pun intended), the meanings of the houses in the 8-House System get blended with the meanings of the houses in the 12-House System. In the 8-House System, the 7th House is marriage and the spouse but in the 12-House System the 7th House is marriage while the 10th House is the spouse.
This tells you very early on there are transmission errors creeping into astrology. We wanted to show you how that happens. We’ll discuss decans in greater detail later providing our reasons why we reject decans and you can examine the sources and decide for yourself.