Reading two books concurrently;
The Presocratics, edited by Philip Wheelwright
The First Philosophers; The Prosocratics and the Sophists, translated by Robin Waterfield
They both go through the Greek presocratic philosophers. I'm going back & forth between the two books one philosopher at a time.
Really I want to study Aristotle. However, I didn't want to just jump immediately to Aristotle without getting the the academic basis he had to work from. So I started with Homer, then Aesop, and now these guys. Next will be Socrates / Plato, then finally to Aristotle himself. Eventually I'll end up going through the Stoics, but I'll use some caution with them. The Stoics have such a well thought out world view, it's tempting to join them.
I thought the Presocratics would just be a stop along the way, but I'm really appreciating them in their own right. They come from a time when philosophy and science were still considered to be the same thing. They ask questions that no one before them had thought to ask, at least among those whose work has survived in the written record. They move forward from the anthropomorphic views espoused by Homer & his contemporaries. They want to know what is the basis of the world / universe, what is a human, where is the earth located; metaphysical questions like that. It's Socrates who will turn the philosophical questions towards how a person should live; these guys were still just figuring out what a human was.