Slippery Slope:
That grey area concerns me.
Intellectual Theft?
Also, the desire to require people to pay for what might be intellectual theft is dangerous.
Disney Theft
For example, allegedly, according to a book, it is said that Walt Disney stole art from his business partner around the 1920's or so. Walt went on to copyright, to patent, his work.
Dangerous
So, I say that to say that some of these things can be dangerous.
Weird Al Robbery
Now, Weird Al would make parodies of famous songs. He has said that he doesn't even have to ask people for permission. Now, he says he does out of courtesy. But he is right that he doesn't have to.
Google Wars
But, currently, YouTube (Google) and others have been attacking people who have made parodies themselves (and other things as well).
Fair Use Act
Parodies and other things may in fact be completely or partly protected under the Fair Use Act in American law for example (depending on the piece, video, details, etc).
I Lost Thousands of Videos
Google terminated three of my YouTube channels which means I lost thousands of videos which goes back to 1996.
Copyright
Copyright can be tough to enforce.
Selective Enforcement
What is worse is when copyright is selectively enforced. Sometimes, in life, one person will come up with what he or she may think is an original idea. Plagiarism is a tricky debate. It is more than a subject and more a subjective war between what might be recycled, reused, stolen, echoed, parodied, and Epstein didn't kill himself.
Nothing New Under Dee Sun?
King Solomon said that there is nothing new under sun around three thousand years ago. For example, if I ask you, "HOW ARE YOU?" Then what? How dare you says Greta, just kidding.
How Are You?
Is the adaptation or the reusing of idioms, common phrases, etc, then theft, etc? Can I ask you how you are? Am I not stealing that phrase? Should I give credit to whoever first said "How are you?" Because other people asked that question. Maybe that is an exception to the rule. But we can debate these types of things all day.
Speeches
Like speeches for example. Like songs that talk about love. And then you have another song that talks about love as well.
Star Wars & Star Trek Spam?
Then you have JJ Abrams who might be recycling some of his own ideas or that of other people as he did Star Trek and as he is doing Star Wars right now.
Piracy?
Pirated videos may or may not be a crime. The actual process of getting it in the first place for example might be a crime, some might say. However, watching pirated videos shouldn't be a crime or isn't, technically. Also, the 4th amendment (privacy) is being violated.
Connecting Dots
But I digress. I see connections and similarities between many different things. I'm connecting dots. I'm going down original oatmeal rabbit trails. So, I say that to say that people may steal things from other people. Sometimes, it is accidental.
Purposely, Maliciously?
Now, it can be tough to prove when intellectual property is stolen on purpose, perhaps maliciously even.
Being Sued
A person, later on, may still get sued or attacked for allegedly stealing the ideas from other people. Some of this can be way too subjective.
Invisible Lines
The subjective line between what might be new and what might be not new is so vague like you said.
Compensate
It is nice when people can pay people for helping.
Generosity
So, if you helped me, then I should send you some money. True. Perhaps. I should not be required. But that would be generous of me.
Money
However, money is not the only kind of money, by the way. Time is money. Good publicity has value as well. Cryptocurrencies has value as well. Gold has value. Salt was used as money centuries ago. So many things can be used as currency. Marketing is valuable. The list goes on and on.
Make Government Smaller
People should try to link to their sources and pay them some money as well, perhaps. That would be nice. However, these things should not be required by federal or international laws. Local laws (for example), maybe in some cases to some extent. But for the most part, federally and globally, I prefer smaller government. So, copyrights, patents, trademarks, etc, can be better enforced/etc as government grows bigger and bigger in a pursuit to keep people allegedly safe through the means of stealing freedom from humans.
Conclusion
So, I agree with you that people should try their best to credit people as much as possible, verbally and financially. So, both is good. In some cases, financial compensation may be earned, collected, gathered, etc, directly and indirectly via verbal citation as marketing has value for example.
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