Tim states: "I believe that Bradley goes too far when he identifies any proprietary software as 'harming users by denying their freedom.'"
Correct, everyone is bound to some degree by software that they choose to use. But it's not that simple, because we are all increasingly bound by software that our employers and governments choose for us. We should all accept that the developers choice of a license does have a great impact on society. Once people begin using software, they develop a certain symbiosis with it. Like learning to speak a language, they can have a hard time switching from one sytem of interaction to another. So, they are effectively locked in by the natural human aversion to change.
Brad's point that propriety software "harms users by denying their freedom" is still true. When we, as developers, choose a license that doesn't protect freedom, then we affect more than ourselves. Not just users either. Proprietary software also harms developers by denying their freedom unless they are the sole copyright holder (which is rare). Most of the developers must agree to whatever terms the owner dictates, even if they don't want to. The developers and users become locked in to these terms, which by nature create groups with power and those without (when the license limits freedom). The owners of the code get to dictate the law. Unless the license protects freedoms, it is harmful to the majority of developers and users.
In short, the license restrictions that we choose as developers can effect generations to come...not just our current users and ourselves. We have an important role in shaping the future of these new laws that we are creating by the code we write...we should seriously consider how we would like our future to unfold.
"The love of liberty is the love of others; the love of power is the love of ourselves." - William Hazlitt