Brian Tomasik suggests, and many people agree, that keeping public records of your important conversations and correspondence is really useful: it makes them easier for other people to discover, give feedback on, search for, and link to, and makes sure (via the Internet Archive) that the information sticks around for a long time.
I completely agree. What’s more, I think we should go further. Not all “public” correspondence is equally useful. Consider the many useful discussions held in Facebook groups like Effective Altruists:
They’re harder to discover. Facebook groups aren’t indexed by Google, as far as I can tell. I doubt that it’s tracked by other sites like StumbleUpon either. This seems to hamper discoverability a lot. While discussing on Facebook helps people in your immediate social network discover the content, it doesn’t help things spread at all.
They’re harder to get feedback on. This is especially true when articles are shared multiple times. I’ve sometimes written posts and seen the same discussion happen in two or three Facebook comment threads and on the comments of the post itself. It would be much better if these discussions could be merged.
They’re harder to search for. Of course, discoverability isn’t the only problem with Facebook’s custom search. Even if you’ve already seen the conversation that you’re looking for, good luck finding it if you don’t know exactly which group it happened in (and maybe what exact time it was).
They’re harder to link to. Some Facebook groups are private. Even when linking to public ones, the URL schema might change at Facebook’s whim.
They may not stick around. Facebook has changed their user interface and data model many times before. Who knows what information will get clobbered in the process? And when it does, is anyone keeping a backup? The Internet Archive certainly isn’t, and this help thread suggests it’s not even possible.
As a result, Facebook discussions have almost none of the benefits of public correspondence that Tomasik’s essay noted. Wherever possible, I recommend moving discussions and correspondence off Facebook, Google+, and other corporate-owned media and into blog posts and comment threads. For instance, if you’re going to comment on a blog post that someone shared, all else equal you should comment on the post itself, not the “share” on Facebook. It’s a small inconvenience with many positive externalities.