Because of books and words, the achievements of the previous generation and those who help future generations will multiply. This is mainly because all mankind has enjoyed knowledge.
The exception is that philosophy cannot be improved. You can find how naive Aristotle's physical theory is now, but his philosophical theory cannot be easily denied.
It is incredible for modern people to learn calculus in ancient times, but the philosophy of modern people is usually not as good as that of ancient times. Just as most famous philosophers are older than scientists.
Philosophy depends entirely on thinking ability, so its grades are quite slow.
It is common for knowledge to go astray, and science is to grow in endless mistakes.