> Textbooks and eyeglasses are guarded by copyright and patent
I'm talking about the physical book, not the words contained within.
> When I buy a house, I can make modifications to it.
When I buy software, I should be able to make modifications to it.
> Microsoft probably wouldn't care if I somehow reverse engineered Windows and modified it for myself only.
That's explicitly prohibited by the license. Whether or not you think they'll enforce the license in your case has no bearing over the fact that it does violate it, and free software advocates argue that such licenses cannot be nonenforceable.
In any case, patents are a separate issue altogether. So is copyright, actually - free software licenses are a way of twisting current copyright law into doing the opposite of what it was meant to do: provide freedom.
Let's take a step back and look at the goals of free software. It's not just to modify and tweak things I own, it's to allow me to modify, enhance and contribute that work back to the community.
By that yardstick, most textbooks and eyeglasses are not free.
I can't improve a textbook and put it online. I can't put my improved sunglasses on the market (even if it was non-profit).
So why are people revolted by a copywrited and patented (hence unfree) OS, but have no qualms using other non-free products?
Personally, I think free and proprietary products can co-exist. Both models produce innovations which ultimately benefit society.
> By that yardstick, most textbooks and eyeglasses are not free. I can't improve a textbook .... I can't put my improved sunglasses on the market (even if it was non-profit).
Yes you can - the product in that case is physical, not digital. You can certainly turn the pages of a book into an origami creation and sell that on a secondary market if that's what you want to do. You can sell modified copies of physical products to your heart's content.
I'm talking about the physical book, not the words contained within.
> When I buy a house, I can make modifications to it.
When I buy software, I should be able to make modifications to it.
> Microsoft probably wouldn't care if I somehow reverse engineered Windows and modified it for myself only.
That's explicitly prohibited by the license. Whether or not you think they'll enforce the license in your case has no bearing over the fact that it does violate it, and free software advocates argue that such licenses cannot be nonenforceable.
In any case, patents are a separate issue altogether. So is copyright, actually - free software licenses are a way of twisting current copyright law into doing the opposite of what it was meant to do: provide freedom.