Many users of the GNU/Linux system will not have heard the ideas of free software. They will not be aware that we have ideas, that a system exists because of ethical ideals, which were omitted from ideas associated with the term 'open source.'

Proprietary software keeps users divided and helpless. Divided because each user is forbidden to redistribute it to others, and helpless because the users can't change it since they don't have the source code. They can't study what it really does. So the proprietary program is a system of unjust power.

The idea of free software is that users of computing deserve freedom. They deserve in particular to have control over their computing. And proprietary software does not allow users to have control of their computing.

Richard Stallman Quotes