A hundred years ago, we learned about the world from our parents and newspapers. Television and… A hundred years ago, we learned about the world from our parents and newspapers. Television and radio began informing us in the middle of the last century, and in the late ’90s, the Internet became yet another source of information.

But even with all this, there still wasn’t any way to find out what people, in general, thought about things. You could read the ideas of professional opinion-makers in print or discuss politics with the neighbors on bridge night, but if you wanted some kind of general consensus — beyond the views of family and friends — on an event or trend, you were out of luck.

The explosion of new media over the past decade has changed this, replacing our former informal-information drought with a deluge of facts about the generic “people.” Our scope is broader than friends and family and now consists of acquaintances, blog writers and anonymous reviewers.

Information comes not only more often (constantly), but also with a specificity unimaginable 50 years ago. Polls, though not new, are shockingly cheap to conduct since the advent of robocalling and the Internet, enabling us to learn almost anything about Americans, from the percentage who think toilet paper should be positioned on the dispenser over the roll to the percentage who believe God or a universal spirit is real (72 percent and 92 percent, respectively). Social networking, too, provides insight into the public’s thoughts and goings-on, so much so that cable news outlets now regularly read news-related Tweets and e-mails from viewers as a form of reporting.

We have, or at least believe we have, a far more intense idea of the pulse of the nation than ever before.

Although this might seem like a victory for freedom of information, it actually represents a potentially dangerous trend. Knowing the popular position on certain ideas can actually cloud personal judgment and concrete facts. In late 2009, researchers from the University of Maryland conducted a study in which they explained the unproven theory of ESP (extrasensory perception) to participants and then told them that it was either popular or not popular with the public, and either accepted or rejected by scientists.

When people were told that the theory was rejected by science but popular with the public, participants were very likely to agree with the idea of ESP. Public opinion, in other words, beat the word of scientists — an outcome that doesn’t speak positively for society’s advancement. And now that the public opinion on any subject can be so easily accessed, this trend will only expand.

One victim has been the economy. The recession, after all, was partially caused by traders collectively believing, against their personal wisdom, that everybody could afford $300,000 mortgages. It isn’t necessarily that they were selfish or dumb, but that traders, bankers and investors all felt a certain sense of security because no other traders, bankers or investors seemed to have any problem with the situation. The cycle fed on itself, despite growing evidence of over-leveraged consumers and rising foreclosures. Eventually, of course, the system failed.

The bankers, although not getting their advice from Facebook, fell victim to the perceived wisdom of the masses. But the problem here and everywhere with this issue is that masses don’t necessarily have the right opinion in the first place.

Traditionally, it is assumed that when people make a judgment about anything, any error is somehow distributed so that somebody else’s opinion cancels it out eventually. When one person orders his porridge extra hot and another extra cold, porridge producers will eventually see that you probably want yourporridge “just right.”

But with public opinion, people don’t make independent decisions. Instead of consciously noting where previous errors were and self-correcting, adherence to the public opinion locks people in. Bad decisions no longer cancel themselves out and good ideas aren’t always the winners. The majority, therefore, is not always correct. Yet as shown by the Maryland study and the economy, it still drives personal decisions.

With the new media here to stay, we need to be more conscious of when our opinions are being driven by public opinion rather than logic and reason. Sarah Palin, the South Beach Diet, Barack Obama, the Tea Party, Justin Bieber and “Avatar” alone all possibly owe some of their success or failures to public swelling that — we can now see — might have been unwarranted. We must all beware the phantom of public wisdom and instead be more willing to trust personal wisdom.

E-mail Nick at [email protected].