Everything you've learned in your life, in school or out; Do you give proper credit to the creator/author/inventor/discoverer of that knowledge, or refrain fro

Everything you've learned in your life, in school or out; Do you give proper credit to the creator/author/inventor/discoverer of that knowledge, or refrain from using it? The question isn't whether this happens to be legal or not, the question is whether it should be, and to what extent. Do you have any example which you were wanting to compare to, or was the question deliberately open-ended?