What happens when two different people have the same idea? Who owns the idea then - the first one to patent it?
If thoughts can evolve out of a group or a culture then it seems to me that patents are just a way of appropriating the means of monetising ideas that come out the broader culture/society/science etc.
The other thing to consider is that patents and IP are often about ideas and this concept clearly does not give as much value to the people who have to realise those ideas and enhance them and bring them to market sensibly.
Just because one person has an idea to do something doesn't mean that someone else shouldn't have that idea also in fact it's very likely.
The idea that one person came up with a great idea in a vacuum and should have sole rights to it's monetisation is rubbish. Clearly they have been influenced by the culture and people around them - should they get some credit too?