eu achei bem mais interessante ler o link http://diveintomark.org/archives/2009/10/19/the-point

É mais esclarecedor que apenas o trecho destacado.

2009/10/20 Everton Zanella Alvarenga <everton137@gmail.com>
A resposta dele para um executivo de uma editora:

"I enjoy working with publishers because it makes me a better writer.
But I don’t write for money; I write for love (or passion, or whatever
you want to call it). I choose open content licenses because this is
the way I want the world to work, and the only way to change the world
is to change yourself first.

I don’t know where that leaves you as a business. But you’ve made a
good amount of money on the original “Dive Into Python,” despite the
fact that it’s been available for free online for 8 years. A German
translation of Dive Into Python 3 is being published this quarter by
Springer/Germany [a division of Apress' parent company] almost
simultaneously with the English edition — much sooner-to-market than
it would have been under a closed development process. (And an Italian
translation was just released yesterday. You should snap that one up
too before someone else does!) So maybe the problems you perceive are
really opportunities in disguise."

O texto completo sobre o livro que ele publicou com uma licença livre,
sobre a linguagem de programação Python, pode ser lido aqui

http://diveintomark.org/archives/2009/10/19/the-point

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