I'm reading Innovation and Incentives by Suzanne Scotchmer, and she makes the claim here at the start of the book (pg. 6):
We know that the ancient world repeatedly discovered and forgot the same inventions, such as central heating and the arch. Partly these failures were due to the absence of printing, without which the recording and dissemination of knowledge is difficult. However, inventors also tended to keep their discoveries secret, so that inventions sometimes died with their inventors. Available evidence suggests that secrecy was especially prevalent in shipbuilding.
Do we have evidence that this was all the case, or is it just a random claim? Were the inventions of central heating and the arch "forgotten" and then found again, and was secrecy so big over inventions?
Thanks!
I'll just comment on the last line "was secrecy so big over inventions?"
Yes, just like many modern nations, the more ancient world used various means to safeguard their source of income, renown, and military strength.
Some secrets were so closely guarded like the production of silk in China and there was plenty of secrecy surrounding Murano glass. Exposing the secrets of those professional trades were punishable by death.