Stallman's argument has always been that he is about long-term freedom; the BSD people, in turn, say that he produces software which is not fully free. They interpret the term free as gratis, its common meaning.
For Stallman, it goes much deeper than that. It may have seemed illogical at the time but he was always thinking long-term and the GNU project has reached 25 in very good shape.
The emergence of open source in 1998 as a term designed to remove the confusion over the meaning of the word "free" in free software has not sat well with Stallman. Though this was to some extent a valid reason, in some cases it was chosen to "appeal instead to executives and business users, many of whom hold an ideology that places profit above freedom, above community, above principle."
There have been some legendary flame wars over the terms "free software" and "open source." They both "describe the same category of software, more or less, but say different things about the software, and about values."
But despite all the arguments, the use of FOSS as it is often called, has grown and grown. At times, the growth has been due to political reasons, at others due to cost. But there is an overriding factor - quality.
Peer review has ensured that a great deal of the software developed by free software projects has been coded well. There are big projects (like Debian GNU/Linux) and smaller ones (like Slackware) but the common trait has been attention to detail.
Nobody can predict the future and it is impossible to say in which direction the free software train will travel over the next 25 years. Many of those who are reading this may not be around to see the next major anniversary. For the time being, we should all thank our stars for the maverick who had the courage to get the ball rolling.All quotes in this article are taken from The GNU Project