I am aware of the philosophical meaning.
Then you should be aware that the way in which you used the term is not in line with its philosophical meaning.
Stating you wish to approach something skeptically without stating exactly what you are approaching seems sensible to me.
This was not, in fact, your original wording. From your original comment:
I am here in a position of scepticism about the claims and projects this site wishes to advance.
Specifically, you singled out "this site", i.e. LessWrong, as the one whose claims you were approaching skeptically, suggesting that there was something in particular about LessWrong which you found disagreeable. The connotations of your original comment and the ones you are offering now are radically different, even if they may be denotatively similar. The practice of picking up on (and sending) said connotations is a crucial element of any social interaction, so if people are apparently interpreting your words incorrectly, you should take that as evidence that you were unclear and seek to be more clear in the future, rather than waste time defending your original wording. A simple "Sorry, you misunderstood me; this is what I actually meant" would have sufficed.
I didn't say anyone had been unreasonable, I just said I feel unwelcome.
Again, your original wording:
I have to add that this welcoming thread isn't very welcoming.
This is not a statement about your own state of mind; rather it is a claim of what (presumably) you regard as an objective aspect of this thread (whether it is "welcoming" or not). Again, your time could better be spent simply providing a clarification rather than arguing that said clarification is what you said in the first place. No need to bring up "I didn't say this; I said that"; instead, just say "I meant to say that".
As a more general statement: LessWrong as a community places extremely great emphasis on clear communication. Often, we find that a good majority of disagreements can be avoided simply by having all participants state their position clearly in the beginning, rather than having said position remain unclear or nebulously defined, eventually devolving into arguments about the definition of a word, or some such. If you view this thread in light of this, you'll see that none of this is intended as an attack, as you (seem to) have been perceiving it as. We are simply trying to encourage clear communication, and clean up misunderstandings.
A few notes about the site mechanics
A few notes about the community
If English is not your first language, don't let that make you afraid to post or comment. You can get English help on Discussion- or Main-level posts by sending a PM to one of the following users (use the "send message" link on the upper right of their user page). Either put the text of the post in the PM, or just say that you'd like English help and you'll get a response with an email address.
* Normal_Anomaly
* Randaly
* shokwave
* Barry Cotter
A note for theists: you will find the Less Wrong community to be predominantly atheist, though not completely so, and most of us are genuinely respectful of religious people who keep the usual community norms. It's worth saying that we might think religion is off-topic in some places where you think it's on-topic, so be thoughtful about where and how you start explicitly talking about it; some of us are happy to talk about religion, some of us aren't interested. Bear in mind that many of us really, truly have given full consideration to theistic claims and found them to be false, so starting with the most common arguments is pretty likely just to annoy people. Anyhow, it's absolutely OK to mention that you're religious in your welcome post and to invite a discussion there.
A list of some posts that are pretty awesome
I recommend the major sequences to everybody, but I realize how daunting they look at first. So for purposes of immediate gratification, the following posts are particularly interesting/illuminating/provocative and don't require any previous reading:
More suggestions are welcome! Or just check out the top-rated posts from the history of Less Wrong. Most posts at +50 or more are well worth your time.
Welcome to Less Wrong, and we look forward to hearing from you throughout the site!
Once a post gets over 500 comments, the site stops showing them all by default. If this post has 500 comments and you have 20 karma, please do start the next welcome post; a new post is a good perennial way to encourage newcomers and lurkers to introduce themselves. (Step-by-step, foolproof instructions here; takes <180seconds.)
If there's anything I should add or update on this post (especially broken links), please send me a private message—I may not notice a comment on the post.
Finally, a big thank you to everyone that helped write this post via its predecessors!