I wonder how you confident you feel that you know what's going on in Syria. Me? I don't feel at all confident.
Maybe I'm just old-fashioned, but I always feel much happier when there are journalists whom I trust on the ground, out there with their notebooks, recorders, and cameras - reporting back to me what they can see and what they can hear.
I'm even happier if I'm there myself - but in Syria, there are no independent journalists operating because none has been allowed in. Local reporters can't work freely, because there are no free media.
And that's why we rely on social network sites likes Facebook and Twitter. Throughout my working day, my computer screen flashes constantly with a never-ending stream of updates from people in Syria and elsewhere, telling me what's going on where they are, now, this minute. It's mesmerising - but it can also be deeply misleading.
If you follow me on Facebook or Twitter, you may remember that six weeks ago I posted a link to a Syrian who called herself "A Gay Girl in Damascus". She wrote unusually vividly and movingly, especially about the day when armed men came to her home late at night to arrest her.
She described how her father stood up to the men, talked to them, lectured them, and shamed them until eventually they left without her. "As soon as the gate shut, I heard clapping; everyone in the house was awake now and had been watching from balconies and doorways and windows all around the courtyard ... and everyone was cheering ... my Dad had just defeated them! Not with weapons but with words ... and they had left ... I hugged him and kissed him. I literally owe him my life."
Then, last Monday, a woman describing herself as the blogger's cousin, wrote that Amina (the "gay girl in Damascus") had been abducted while walking in the streets of the Syrian capital. A huge internet campaign swung into action, mobilising friends and supporters to press for her release.
But here's the point. It quickly emerged that no one actually knew the blogger. No one in Damascus had actually met her, or knew anyone who had. Even her supposed girl-friend in Canada, whom we interviewed in all good faith on the programme on Tuesday, later admitted that she had neither met nor even spoken to her - their entire relationship had been conducted online, via email.
So who is Amina? Is she someone who is hiding behind a false identity, perhaps for her own security, or is she a work of fiction? Does she even exist? (The pictures of herself that she posted online turned out to be of someone else entirely.)
UPDATE: A man called Tom MacMaster has now being the author of the blog.
Does it matter if one blog among millions turns out to be a fake? Unfortunately, it does, especially in an environment where independent reporting is impossible, so that blogs and other online media become the only available substitute.
If Amina does not exist - if she isn't who she says she is, or if the events she writes about didn't happen - then we have learned an important lesson: that we must be doubly cautious when we use the information provided by bloggers and Tweeters as a basis for our reporting. (There's an excellent account of the whole mystery .)
According to human rights groups in Syria, well over 1,000 people have been killed since the current wave of unrest exploded two months ago, and more than 10,000 people are believed to have been arrested.
Yesterday, more than 2,500 people were reported to have fled across the border into Turkey to escape an expected army onslaught on the town of Jisr al-Shughour, where, according to official media, 120 people were killed last weekend in what seems to have been a partial army mutiny.
I wrote eight weeks ago: "If you want to know what's really worrying Washington as officials anxiously survey the anger sweeping through the Arab world, it's not Libya you should be focusing on. Try Syria." It was true then, and it's even truer now.
More than ever, we need accurate information about what is happening there - and more than ever, accurate information is in scarce supply.