I encounter this assumption repeatedly in writings on the subject, hear it repeated in documentaries, echoed in peoples conversation. Why is this taken for granted?"Just as the earlier witchcraft, or worship and conciliation of evil (let's just ignore that comment, shall we?), overlapped in many places the newer Shamanism, so the latter overlapped the beautiful Nature-worship of the early Aryans, the stately monotheism of the Shemites, and the other more advanced or ingenious developments of the idea of a creative cause."
I had a friend in college who was working on his Masters degree in mathematics & drove a bus to pay his tuition. Sometimes I rode his bus so that we might chat while touring the New England countryside -- very nice. Most of the time, I did not understand what he told me about mathematics. However, he opened my eyes to one concept which, after an initial shock, made perfect sense. It has remained with me since. He said we make assumptions & understand our universe in a base 10 system only because at some point in history our ancestors decided ten was a good number -- which it is for an animal with ten digits. However, any number is suitable to use as a base in mathematics. Any other number could serve as our base & it would seem quite natural had we been using it all this time. The message here is this: our understanding of systems of value, our perception of progression is shaped by our base number, our elected foundation. Our foundations were chosen for us long ago, so we take them for granted, but what if they were different?
Let's just imagine that a team of anthropologists from a highly "advanced" alien society arrived on Earth to study human culture. These aliens are polytheists with a complex system of worship & belief that reflects their "sophisticated" civilization. What might they, probably seeing themselves as more enlightened, (after all, they did travel across space to study us) think of our largely monotheistic systems? I imagine them saying, "These humans are simple creatures. The need an uncomplicated dogmatic, religious ideology: they imagine themselves overseen by a single, all-knowing, absolute godhead, subscribe to a rigid & hierarchical system of worship & moral conduct all of which is based upon the expectation that they will embrace this system with out proof of validity. They call this 'faith.' Our conclusion is that these creatures cannot comprehend or appreciate the vast complexity that is the true nature of the cosmos." Or something like that.
How does "progress" look from an alternate foundation? Different? You bet. As an animist who also accepts polytheism, I must take offense at being relegated to the "primitive" state by assumption. In fact, I must question the whole premise of any progression at all. Really, who said so? As long as we defer to this mode of thought, we will automatically place value a judgement on each persons spiritual beliefs. This thinking demands an appraisal of human spirituality as falling on a gradation -- from rudimentary, crude & simplistic to refined, cultured & modern. In the end, it is really sad for everyone, not just the lowly Shamans & Witches (or Pagans, Druids, Heathens, Wiccans, etc.). Hierarchical value judgements deem some faiths illegitimate while corroborating the alleged "supremacy" of others. Human relationships are compromised as mutual respect is eroded. All this because we subscribe to a base value that was assigned by someone -- more primitive & archaic than ourselves -- long, long ago.