The Histories by Herodotus was life changing for me (see my handle!). But, be aware that it has to be a good translation: the online free ones are not the ones you should read.
Why? Because until I read it my only other experience with writing of that era was the bible readings from when I attended synagogue (before I realized that there was no god). I always found the bible stuff strange, but I forgave it, because I thought that people were just like that at that time in human history. Well, Herodotus changed my mind. He is brilliant, skeptical, humorous, and inquisitive. Attributes that, until I read the book, I somehow thought belonged to we moderns. Now I know how wrong I was, and I think about things differently.
It is obvious in hindsight but it was a revelation for me that the ancients were not idiots/have something to teach us, and how little progress there is in a non-technological sphere since then (e.g., political social issues from many 100s years ago are still relatable or the stoics wisdom is still applicable at the personal level)
Well, we genuinely do have a far better understanding of the natural world than the ancients. Many practical problems they faced have been effectively solved by technology, like food scarcity, communication, transportation etc. To me it seems more surprising that there hasn't been similar progress in our understanding of society and the human condition. We're still struggling with most of the same issues they were.
That is mostly my point. What conclusion can you actually make about any other society, current or historical, on the basis of "our practical problems being mostly solved by technology"?
I think the danger in this focus on technology now is that it is so easy to dismiss anything at all that ancient Greeks or whomever said as not even simply wrong but even trivial and unworthy of being studied.
Of course I used to dismiss most earlier writings as well. What could they possibly teach me, after all everything is so advanced now? This kind of attitude being widespread and I think entailed in most modern science talk (as an unspoken and easy conclusion that mostly never becomes explicit) is part of the reason we struggle with the same issues as you say.
The logic why I thought so is simple: I'd read Aristotle views on physics initially (complete garbage) and assumed if one part (that I can easily verify) is garbage, then other parts (that are not so easily verifiable) are likely to be garbage too.
If I see something wrong published on the topic that I know well, I assume that the quality of the content from the same source is not any better for the topics I don't know.
It is a good general principle but the heuristics/shortcut doesn't work sometimes.
May I recommend reading them in their original languages?
It becomes impossible to truly appreciate a completely different culture, and way of thinking and seeing the world, when it's being tortuously twisted to fit into the "English" way.
It's like reading Bulgakov's The Master and the Margarita in anything but Russian; or Clauswitz's On War in anything but German; or Homer's Iliad in anything but Ancient Greek.
In the first, you lose the raw emotion of the Russian language. In the second, you lose the exacting precision of the German language. And in the last, you lose the sublime beauty of the Ancient Greek language.
Why? Because until I read it my only other experience with writing of that era was the bible readings from when I attended synagogue (before I realized that there was no god). I always found the bible stuff strange, but I forgave it, because I thought that people were just like that at that time in human history. Well, Herodotus changed my mind. He is brilliant, skeptical, humorous, and inquisitive. Attributes that, until I read the book, I somehow thought belonged to we moderns. Now I know how wrong I was, and I think about things differently.