As stated in the previous post, I have become an instant expert on intellectual property, or at any rate I need instantly to become an expert on the expertise of others on this subject. Here's my first shot at it. Tell me what I've got wrong, if you've a mind to. Or if that would be quicker, tell me what I've got right. Be as severe as you like, I won't mind. This is not my Last Word on the subject, it is my first throw of the dart at the dart-board.
So, to begin:
It is often said that we "should see both sides of the issue" as if that was automatically a virtue, and maybe if is, if there are only two sides. But life is seldom that simple, and with the matter of intellectual property rights I believe we can discern a minimum of three sides to the argument, each of which I shall now caricature.
Position One: Capitalism and free markets are wonderful, and are responsible for all the economically good things in the world, and without property that can be no capitalism, and no markets. What is more, property rights in what you (or others whom you have traded with) have created with intellectual effort are no different from property which consists of physical stuff or which has been created by applying physical labour to physical stuff. If you thought of it and wrote it down, or recorded it, or filmed it, then it's yours, and anyone who uses it without your permission is no different morally, and should be treated no different legally, to someone who steals your car or your clothes or your bank balance.
Position Two: Capitalism and free markets are evil, and are responsible for all the economically bad things in the world, and without property that can be no capitalism and no markets, and that's good. All property is theft, including "intellectual property". However, the times being what they are, we can't publicly say that we want to smash capitalism, all of it, and expect to get much of a hearing from civilised people. So we must sneak up on capitalism, attacking it at its weakest points. One of which is "intellectual property". People are less willing (see Position Three below) to mount a robust defence of intellectual property, and this is therefore one of capitalism's weak spots, which we should attack it fiercely, making whatever use we can of Position Three arguments, even though we actually despise these arguments as pro-capitalist, pro-free-market gibberish.
Position Three: Capitalism and free markets are wonderful, and are responsible for all the economically good things in the world, and without property that can be no capitalism, and no markets. However, "intellectual" goods are not like the usual sort of goods. If I use your car, you cannot simultaneously use it. But if I use your idea, you are not thereby prevented from using it. You know when someone has stolen your car, but it may be years or never before you realise that they have "stolen" your idea. Ideas are not scarce. What is more, they are now extremely easy to copy. Maybe intellectual property rights were once upon a time necessary to ensure that creators, inventors and innovators were rewarded for their creativity, inventiveness and innovation, but in the new digital age, such restrictions are no longer necessary. If you proclaim an idea, and that idea reaches people with whom you have no contractual relationship whatsoever, by what right may you forbid them to act on "your" idea? And how do you propose to enforce "your" intellectual property rights, if not with a huge apparatus of state power, such as would threaten capitalism and free trade rather than defend it.
Very few people adopt any of these extreme positions in their pure form. Most veer more or less strongly in the direction of one while seeing the force of at least one of the others. For whatever it may be worth, the only thing I am sure of is in rejecting Position Two. I am attracted by the idea of a world dominated by Position Three, but suspect that this may never be either possible or indeed desirable. It seems to me that … But no, I'll leave any more of that for later.

