I want state here on fact, the "copyright" is an rather new anglon-saxon invention and was only later imported to Germany[1]. Interestingly, the era of the "land of poets and thinkers" and the economic rise of Germany was boosted by the fact - that there were no copyrights laws which hindered. Authors had to publish good and more work.

[1] https://en.wikipedia.org/wiki/Copyright#Background

Quote from Wikipedia

Printing brought profound social changes. The rise in literacy across Europe led to a dramatic increase in the demand for reading matter. Prices of reprints were low, so publications could be bought by poorer people, creating a mass audience. In German language markets before the advent of copyright, technical materials, like popular fiction, were inexpensive and widely available; it has been suggested this contributed to Germany's industrial and economic success. After copyright law became established (in 1710 in England and Scotland, and in the 1840s in German-speaking areas) the low-price mass market vanished, and fewer, more expensive editions were published; distribution of scientific and technical information was greatly reduced.

And from the history arctile

Heinrich Heine, in a 1854 letter to his publisher, complains: "Due to the tremendously high prices you have established, I will hardly see a second edition of the book anytime soon. But you must set lower prices, dear Campe, for otherwise I really don't see why I was so lenient with my material interests."

It is not okay to claim other works as yours, publish private material or just don't give you a fair share upon your work. Probably we should have opted for another approach than "copyright" or "patents". Luckily the US at least got "Fair Use" and maybe the idea of a "Culture Flatrate" from Germany is also a good idea.