I have just read the fine blog post, which taught me the term "need for cognition." Having read it, I posted a Facebook link to the blog post visible to my 554 FB friends titled with the question, "The suggestion of one research finding is that people who like to use social networking sites don't like intellectual challenge. Can you think of any counterexamples?" I will see what happens over the next several hours.

The use case I see most frequently on Facebook among my circle of FB friends is posting links to external publications to elicit discussion--the general use case here at Hacker News. I think people with need for cognition can learn from Hacker News, and if they shape their Facebook friend list intentionally they can learn from Facebook. The second person to Facebook-friend me, connections with whom drew me into the majority of my friend list on Facebook, is a parent I met at conferences on education of gifted children, an occasional participant in email discussions of parenting issues and education reform issues. Over the years I have developed a lot of email relationships (the old-fashioned term would be epistolary friendships

http://onlinelibrary.wiley.com/doi/10.1111/j.1754-0208.2006....

for friendships maintained mostly by writing letters) with parents all over the world who are frustrated by anti-intellectual school systems and who want education for their children that challenges their children intellectually and helps them learn at full speed throughout childhood. In such a friendship environment, I encounter a lot of intellectual challenge. I have to LOOK IT UP if I make a factual assertion that differs from what someone else thinks (much as many people do here on HN). My friends are not screened by occupation, place of birth, country of citizenship, political persuasion, religion, or any other criterion but interest in pursuing learning and improving education for everyone.

I think intellectually curious people make use of Facebook as "free riders" in much the same way they used to make use of AOL as free riders. (This is not even to mention the number of people who learn from HN without posting much here.) I can well believe that many people waste a lot of time on Facebook, so much so that my slogan in Facebook comments is "Friends don't let friends play Facebook games," but high use of social networking sites (FB or HN) is at most a correlate of lower intellectual engagement at the group level, rather than lower intellectual challenge being an invariant outcome of heavy use of social media. The study design reported in the submitted link is not an adequate study design

http://norvig.com/experiment-design.html

to make the claim that all persons who use social media a lot fail to challenge their thinking.

P.S. By the time I had finished typing this comment, I had already received a reply to the submitted link on Facebook: "Well, I don't know people's IQ's, but many of my friends on FB have graduate degrees and almost all of them have bachelor degrees. I think it can provide an extra outlet for those of us who want to have more intellectual discussions and may be limited by our day to day/ face to face interactions." The writer of that comment is a very smart woman now living mostly as a stay-at-home mom for her exceptionally gifted young children (one of whom has been a pupil of mine in the mathematics courses run by my nonprofit organization). As I just edit this comment by adding a few more details, I see other replies challenging the assertion that heavy users of social media are in all cases persons who avoid intellectual challenge.

P.P.S. after further edit: A recent comment from a FB friend is "Does the fact that there are multiple Rhodes Scholars on my friend list (and they have regular activity...) count as data?" Of course, that friend knows that that doesn't exactly count as data, but then another friend commented, "Perhaps the high-NFC subjects of this particular study just couldn't find other high-NFC friends on FB." It surely does matter how intentionally one seeds one's friend list and how one models intellectual behavior on FB.