AceJohnny's Journal: GPL vs BSD

Still today, in mid-2007, more than 18 years after the publication of the original GPL, and about the same time for the BSD license, people are still arguing about whether the GPL or BSD is the most free (as in speech) license.
Let's make is simple: BSD allows you to do much more with the code, at the expense of the freedom provided with subsequent modifications of the code. GPL restricts the way you can use the code, so that subsequent versions can enjoy the same freedom. GPL really is as free as can be, provided that freedom stays intact.
So there is more freedom with version N of BSD code than there is with GPL code, but you have no guarantee for modification N+1 of BSD code, whereas GPL code stays just as free.
Ask HP-UX users if they enjoy the same liberty with their system's code as HP did. Then ask GNU/Linux users if they enjoy the same liberty as the kernel hackers.

This has an impact on the quality evolution of software released under those licenses. With a BSD license, you can never insure that the original code will enjoy improvements made by licensees. You can always, technically, bring those improvements back to the original GPL code.

BSD code will be used far and wide. You'll get nice warm feelings to know that your code was used in the PS3, for example, though you'll never get to try it yourself, as the modifications will never come back to you. If you'd rather have that nice warm feeling, knowing that you helped out other people out of pure altruism (even if it enabled them to make billions of dollars[1] and they didn't give a cent back to you. Yeah, I'm flaming), then go BSD.
GPL ensures that everyone continues to enjoy the same liberty. As such, all changes are public, and can make their way back to the original source. So if you want your code to continue to improve from other's contributions, go GPL. Of course, this'll be at the expense of how far your code will spread, but otherwise that further spread won't benefit you (or your code). That warm feeling won't be as strong, but your code, your baby, will be better off.

If you really believe in freedom, what's the use of a freedom you can't ensure will last?

And by the way, downloading that pirated version of Spiderman 3 is the same copyright violation as using GPLed code in a proprietary application.

[1] at one point Windows' TCP/IP stack behaved identically to a BSD's, implying identical code.

[edit] About libraries: Not all GPL code is stand-alone. Some of it is part of libraries, and in this case, the GPL does strongly limit the use of the library in more ways than for stand-alone software. Libraries are components of larger software, and they are worthless by themselves. The GPL restricts the use of a library in that you cannot use it in non-GPL software. It is viral in the way that to use a GPL library, the whole software has to become GPL. The LGPL license exists so that you can still have a library under a GPL-like license, but it doesn't extend to the application using it.