Intellectual Property is a poor term to use. This is just a generic label used to roll up different protection schemes in an attempt to make them all look the same. They are very different.
Trademark law, for instance, protects your name. There are, of course, fair use provisions. And if your name enters common vocabulary, the good of the people wins and you lose exclusive rights to the mark.
Copyright law protects your work. There are, of course, fair use provisions. It's really designed to protect you from commercial exploitation.
Patent law sucks, IMO, because it lacks the fair use provisions. If I think of a great invention that you've already thought of and patented, I can't even build it myself without running afoul of the law. This is true even if I've never met you, seen your version of the invention or heard of your patent. With 6 or 7 billion people on the planet, it's hardly surprising that more than one person can come up with a given invention. Giving sole rights to that invention to the first person is just the state propping up an unfair monopoly.
The modern patent system is basically good for one thing: warfare between megacorporations. Individual inventors are hardly protected these days - most of them work at the megacorporations, earning paltry salaries, and the moment they have a good idea, the megacorporation gets the rights to it because of their employment contract.
It's a nice idea in the abstract, perhaps, but it has real world problems. Remember that the point of Copyrights and Patents is to encourage people to share the useful arts. The moment these systems actually run contrary to their stated goal is the moment they should be dissolved.