Pink dolphins are my idea, and I refuse to let anyone else think of them. Anybody who does think of pink dolphins must pay a royalty fee for each time they think of pink dolphins, multiplied by the number of pink dolphins they think of.
That last paragraph is a simple – and absurd – example of why so-called intellectual property is an oxymoron. If it’s intellectual, it can’t be property. The concept is based on the premise that ideas can be treated as things, and that’s just not true.