Received wisdom is knowledge generally accepted as true but sometimes is not. Previous generations were educated to think critically, to question information that did not seem logical, to not believe everything they hear without question. Students were encouraged to debate and discuss. Not anymore. Now students receive wisdom and if they don't accept what makes no sense to them, are shouted down.

Over the past two decades, Americans received quite a lot of wisdom about Global Warming. But when the planet's temperature didn't cooperate with the hockey stick model agreed upon by "consensus" scientists, Global Warming quickly quickly morphed into "Climate Change". Off the gullible went like lemmings over a cliff. Climate Change became the new mantra. Only a few asked if the climate had "changed", what had it changed from? What was it changing to? In other words, what is normal? The Ice Age(s)? The Medieval Warming Period? Those who questioned the "consensus science" were quickly labeled "deniers". Hell yes, we're deniers. Where's the proof?

But Global Warming nee Climate Change isn't the only wisdom we've received in the past fifty years. Two obvious examples.

Received Wisdom and Christian Soldiers:

Recently, the President warned Christians not to get on their High Holy Horses about ISIS lopping off heads or burning people alive since 920 years ago, Christians engaged in"Crusades" and Inquisitions. Whether ISIS would have beheaded the 21 Coptic Christians anyway is debatable, but that the Radical Islamic Terror Group used the President's condemnation as a justification for the murders is not.

For those who might believe the Copts were crusaders in the President's terminology, Coptic Christianity was introduced to Egypt by St. Mark during the reign of Emperor Claudius in 42 CE, 528 years before Mohammed was born. To a feline way of thinking, it's Islam and ISIS who were the crusaders.

Were the crusaders a bunch of Holy Rollers intent upon taking the peaceful Muslim lands as the President suggested? The history is a little more complicated than Received Wisdom would have us believe. Jericho (whose walls were supposedly trumpeted down by Joshua) was a walled settlement in 7000 BCE, BCE being the new, politically correct term for the time before Christ was born.

In  2000 BCE, a tribe led by a man named Abraham settled in the land they designated Judea. Five hundred years after that, the Judeans relocated to Egypt where they remained for 260 years before returning to what once was their homeland. Over the centuries, Judea and Israel were conquered by Assyrians, Babylonians, Macedonians (Alexander the Great). The Jews returned to rule after Alexander and held the land for 103 years before civil strife allowed an opening for the Romans. Jesus Christ was born there and in 33 CE was crucified, giving rise to a new religion--Christianity. In 380 CE, 190 years before Mohammed was born, Emperor Constantine proclaimed Christianity the state church of the Roman Empire. The Arab armies of Mohammed conquered the land a couple of hundred years after that and 400 years later, the Pope Urban II decided to try to take the lands back.

So before one receives any more wisdom from the President and the Academic Political Class that benefit ISIS's claims, one must decide for him/herself whether the term crusaders is applicable.

Received Wisdom and a Pox on Your House:

Received Wisdom (some might call it Propaganda) is not confined to Crusaders. In what appears to be an ongoing attempt to denigrate Western influence, received wisdom also informs the gullible that invading Europeans -- those pesky Christians again -- deliberately knocked off the native population of the Americas by passing out smallpox-infected blankets. But the smallpox virus is fragile and dies within 24 hours outside a human host, sooner if exposed to direct sunshine. Unlike Ebola and other deadly viruses, only humans act as a reservoir for the smallpox virus ergo the virus could not have survived on blankets. Since the smallpox vaccine was not developed until 1798, and it probably took a number of years before it came into general use, those who participated in conquest via infection would have been exposed too. With smallpox carrying a fatality rate of 30% for ordinary smallpox and 100% for flat or hemorrhagic smallpox, it's doubtful there were many volunteers to make like Typhoid Mary. So while it is probably true that smallpox decimated the native population of the Americas, it is equally unlikely it was deliberate.