Note: "Open Source" does not have a philosophy[1]. The free software movement does (it has a philosophy based on software freedom), but the "open source" movement does not discuss any of the ethical reasons why users should have freedom (it only discusses practical issues). Personally I think that the "open source" split is one of the reasons that the state of free software is so worrying today.
[1]: https://www.gnu.org/philosophy/open-source-misses-the-point....
http://penguindreams.org/blog/the-philosophy-of-open-source-...
TL;DR is that we have a lot of corporate open source now for infrastructure, but the golden age OSS end products people hoped for in the 90's/00's never really happened.