I'm a 30-yo french man, working as a Free Software developer (mostly in Python and C) and system administrator, deeply interested in "science" (maths, physics, biology, computer science, ...) since as far as I can remember. I define myself as a rationalist and a humanist.
What I value is not easy to explain in a few lines, but to say in three words I would say : humanity (human beings, or any sentient being able to show the quality of humanity like altruism and curiosity), truth (making the map closer to the territory, to use LW terminology) and progress (the idea that we can make the future a better place than the past).
I discovered Less Wrong through... "Harry Potter and the methods of rationality" which a fellow free software developer pointed me to, and I started reading the sequences since then. I find them deeply interesting. I'm not yet fully convinced about the Singularity (or least, it being in a mater of decades and not of centuries or more) nor about trans-humanism, but I do view them with a positive, if yet doubtful, glance.
As for how I went into rationality... well, I was more or less born into it, my parents being maths teachers. My studies in maths and physics (before switching to computer science) and my childhood love of science-fiction probably played a big role in that too.
But it also comes from discovering than in order to pursue "progress" and to protect humanity, we need to make our map reflect better the territory. I then added "truth" to my core values. As Eliezer said, you need something to protect.
Before discovering LW, I was a "traditional rationalist", but I'm slowly evolving (or at least, I think I am, but I may be only believing that I believe...) to a "bayesian rationalist" in reading the posts.
Good day to everyone !
Welcome! Great to have one more LWer from France, potentially one more person to talk to at our infrequent meetups. Are you in or near Paris?