Intelligence is often equated with education and thereby creates a wrong impression. Intelligence is the ability to perceive and retain knowledge and information, not the amount of education one has received. The other misunderstanding is that the first humans were dumb, meaning their capacity to reason and planning were slowly developing over the ages. We must realize that we are not talking about intermediate species. When we talk about the first Humans. We mean the creatures with a fully developed human brain who had the same capability as modern humans. Other human species did exist, such as the Neanderthals and others which are now extinct. We are talking about our branch only.
The reason that I bring this up is that I have received so many comments, by believers in the Bible or the Koran that these books contain correct references to the universe hygiene which they could not have known was knowledge imparted to them by God or Allah. They presume that the human brain couldn’t have figured these things all by themselves.
Others have argued that the connecting between moon and tides, the sun and the seasons would not have been possible when they were so uneducated.
Our forefathers were smart and could make logical conclusions on the same level as we do. They didn’t always draw the correct conclusion so they had to change their mind. Since writing was not invented yet, their knowledge obtained by experience and trial and error was often lost or distorted when was passed on to the next generation by Shamans, story telling, songs and dances. Real knowledge increased slowly until written records appeared. The recorded knowledge, some correct and some not quite true, appearing in the ancient text is the result of past experiences and trial and error, not divine knowledge from an imaginary supernatural Deity. If they were it begs the question why the almighty would not have given us all the knowledge we have obtained so far, at the same time and why some it didn’t pan out.
The passages that the believers try to use as proof that the Holy Books are true and written by their Deity are often written in obtuse language that need extensive and often distorted interpretations, the same as many prophesies do, to make the point. They also conveniently leave out the many cases were the wrong conclusions were made because their experience at that time, was not sufficient enough to come up with correct answers. Because writing is a very, very recent development, we can be sure that an enormous amount of previous discoveries, which we could use right now, have been lost. Even many written records have been accidently or deliberately destroyed. We have the capacity know to judge which of the surviving material is useful but also to judge which material has been superseded by more current discoveries. Religions often are detrimental to the acceptance of new knowledge and that can be very dangerous. A small example of that is parents, who rely on prayer to cure their child, when modern medical knowledge is available for a cure.