It is so easy to take for granted all the modern inventions we enjoy (without having done anything to create) while ignoring the accomplishments of earlier times done under much less favorable conditions. The output of ancient writers and thinkers is amazing when you consider the conditions they had to deal with—Herodotus, Thucydides, Plato, Aristotle, Cicero, Livy, Galen, Ptolemy, and many others. Likewise for thinkers of the Middle Ages and Renaissance.
"Hero's engine" was a steam powered rotating sphere invented two thousand years ago. Just try to imagine what life would be like now if the steam engine had been perfected two thousand years ago.