Even the Bible is based on principles from Greek philosophies like Stoicism, Platonism, and Epicureanism. I read broadly and frequently. Many books I’ve read contained overlapping concepts, which I find very useful for reinforcing that knowledge in myself. I study anthropology, psychology, computer science, ancient philosophy, and much more, because I love to have at least a basic understanding of most things. It allows me to connect with almost anyone. As I learn, I’m able to draw connections across subjects and start seeing deeper concepts coalesce. I needn’t retain every word of what I read, because it’s the most useful takeaways that stick. If I recall just one significant piece of knowledge from a book, it has not been read in vain.