Meh, I'm with abaris - this was a time where superstition was the norm, European science was a mere toddler, and people were by and large ignorant. Even Issac Newton would be working on alchemy over half a century later. John Locke was still a young man. Empiricism is certainly older than that, but it had not been fully embraced in the West.
That book is a product of its time.
That book is a product of its time.