The terms 'free software' and 'open source' are often used interchangeably, but those attending Richard Stallman's presentation at the Australian Computer Society Victorian branch forum last week were left in no doubt about his view of the philosophical difference.
The benefits of open source are presented in terms of practical values such as reliable software, he said, but the free software movement prefers freedom to utility. This, he explained, is because free software can always be improved, but you can't regain the freedom you lose by using non-free software.
The two camps therefore have a very different view of proprietary software. It's becoming increasingly common for companies to run proprietary software such as the Oracle database on GNU/Linux (Stallman takes exception when people refer to the operating system as Linux for reasons we'll explain later), but that's not acceptable to a free software advocate. To explain why, we must first examine Stallman's definition of free software (derived from the GNU.org site), which involves four freedoms for the user:
The freedom to run the program, for any purpose (freedom 0).
The freedom to study how the program works, and adapt it to your needs (freedom 1).
The freedom to redistribute copies so you can help your neighbour (freedom 2).
The freedom to improve the program, and release your improvements to the public, so that the whole community benefits (freedom 3).
Without these freedoms, using software presents people with ethical dilemmas. If a neighbour sees you running a program, realises it would be useful and asks for a copy, what do you do? If the program isn't free, you have to choose between two evils: either be a bad neighbour by not helping, or violate the software licence. The latter is the lesser evil, he argued, because the organisation supplying the software has already done something bad to you by supplying proprietary software, but you would still be going back on your promise. Furthermore, you are spreading more copies of non-free software that will present a similar dilemma to the recipients. The answer, said Stallman, is to only use free software.
A spirit of goodwill is a society's most important asset, he argued, as it makes the difference between a humane society and a dog-eat-dog jungle. Some organisations are "poisoning" this resource, he said: "they are the terrorists, and we have to bring their terror campaign to an end".