Perception is a topic that has always fascinated me. When a person is revered, the reverence quickly disappears if something happens that changes the public’s perception of that individual. If, for example, the person on the receiving end of the adulation is exposed as a fraud or falls into disgrace, admiration soon turns to contempt.

I thought about this while watching a show about Roman Emperor Caligula (a.d. 37-41) on History. Caligula’s given name was Gaius Caesar Augustus Germanicus. When he was a little boy, his father, Germanicus, dressed him in the military uniform of the day, including sandals called “caliga.” As a result, the troops nicknamed him Caligula (“Little Boots”).

Germanicus was the JFK of his time, a charismatic figure who was loved by the Roman citizenry. Emperor Tiberius, fearful of his popularity, sent him off to Asia to kick some butt for the Empire, and he later died in Syria under rather mysterious circumstances that many assumed had been engineered by Tiberius.

Ultimately, Tiberius had Caligula’s mother and two brothers put to death, and, after years of torment and being shuffled from one relative to another, Caligula was brought to live at the emperor’s palace. For reasons that still puzzle me, Tiberius named him as co-heir, along with his cousin Tiberius Gemellus.

After Tiberius’s death, because of their fond memories of his father, the Roman people were wildly excited when Caligula ascended to power. It was the way a large percentage of Americans might have felt had John F. Kennedy Jr. been elected president.

Shortly after becoming emperor, Caligula had his joint-heir, Tiberius Gemellus, “eliminated.” But no one seemed to see this as a sign of things to come. Probably the main reason it was ignored was that he lavished money and other goodies on the people of Rome — and, much like today’s government-dole recipients, they adored him for his “generosity.” It was a veritable love fest.

Then, suddenly, Caligula shifted into a different mode and began a reign of cruelty and depravity that was extreme even by Roman standards. As a result, the people soon came to fear and hate him. Ultimately, after less than four years in power, his own bodyguards stabbed him to death.

Did something happen that caused Caligula to suddenly go insane? There has been much speculation about it over the centuries, but no one will ever know for certain. Regardless, when the perception of the man changed, adoration for him was replaced by hatred.

A modern-day analogy to Caligula could be O.J. Simpson, who for more than two decades was an all-American role model beloved by millions. A mutual friend once introduced me to O.J., and I recall thinking what a really nice chap he was. But once it became clear that he savagely butchered two innocent people, my perception of him changed dramatically.

Most people think of the O.J. of today as a narcissistic, violent person with no moral foundation or conscience. Now that he is finally in prison (for committing an unrelated crime), what is your current perception of O.J. Simpson?

Another good example is Mark McGwire. McGuire was the Paul Bunyan of baseball, hitting an unfathomable seventy homeruns in 1998 to shatter Roger Maris’s record of sixty-one. But what made him such a legendary figure was his nice-guy image. Who can forget his climbing into the stands to hug Maris’s children after breaking their father’s record?

But when McGwire testified before the House Government Reform Committee as part of the Congressional investigation of steroids in sports, he was so evasive that people saw it as a de facto admission of his guilt. McGwire came across as a sullen, weak man, far from the strong, pleasant persona of his playing days. What is your perception of Mark McGwire today?

Unfortunately, no matter how hard we try, most of our perceptions of people will be misguided a significant percentage of the time. It’s one thing to be off target occasionally, but quite another to be consistently wrong. That’s because the foundational principle of all other success principles is having an accurate perception of reality. Which means that great achievements are virtually impossible if one’s perception of reality is perpetually faulty.

The best antidote to this potentially fatal condition is to pay more attention to what people say than to what they appear to be. In other words, don’t be taken in by credentials, demeanor, or reputation. Hey, you can’t get much better credentials than being emperor of Rome, and just about everyone got misled by Caligula.

Likewise, just because someone doesn’t have great credentials doesn’t mean he doesn’t possess skills or wisdom. Some of the best insights I’ve heard over the years have come from “no name” people.

There is no magic way to sort out worthwhile information from junk. The truth of the matter is that it’s up to you to weigh the content of people’s words and make good decisions about them. And to do that, you have to be vigilant about not becoming mesmerized by superficial appearances or credentials.

In the words of Buddha, “Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense.” It’s something to ponder as you go about trying to deal with the delusions that are being offered up by politicians, media talking heads, and so-called experts on a daily basis.

Assume nothing to be true. If your mother says she loves you, check it out.