You don’t need to know the science of why people are so gullible. In fact, when I did a web search for the simple question this was the first article that came up: and I didn’t even use the word incredibly:

Our brains don’t let piddling little facts get in the way of a good story, allowing lies to infect the mind with surprising ease.

If you ever need proof of human gullibility, cast your mind back to the attack of the flesh-eating bananas. In January 2000, a series of chain emails began reporting that imported bananas were infecting people with “necrotizing fasciitis” – a rare disease in which the skin erupts into livid purple boils before disintegrating and peeling away from muscle and bone.

According to the email chain, the FDA was trying to cover up the epidemic to avoid panic. Faced with the threat, readers were encouraged to spread the word to their friends and family.

The threat was pure nonsense, of course. But by 28 January, the concern was great enough for the US Centers for Disease Control and Prevention to issue a statement decrying the rumour.

BBC

There are numerous quotes from P.T. Barnum about what he thought of the lack of their ability to think critically (here).

Likewise there are many quotes on this subject from H.L. Menkin (here). Many of them address politicsand social policy.

Two companies flood evening television with commericals selling what is basically nothing more than modern day snake oil or an overpriced way to get a vitamin supplement no better than store brand multivitamins.

In fact, when the snake oil of old had cocaine, alcohol, amphethamine, opium, or even rattlesnake oil as ingredients, as some did, they probably actually did something healthwise aside from causing addiction.

Prevagen is a hoax as this NBC News article explains.

Now doubt people swear by it because of the placebo effect. One of the ads that is particulary galling to me is the one of David, the phamacist who claims how much it has improved his memory:

Who would want their prescription fill by a phamacist with an admitted memory problem?

There is no better sales representative from show business for selling anything than Donald Trump. Not William Schatner with highly produced amusing Priceline commecials like this…

… or Tom Seleck selling mortgages for AG, no doubt for gun lovers who know about his association with the NRA:

There’s a reason Maggie Haberman, who has one of the weirdest love-hate relationships with Trump, caller her bestseller book about him “Confidence Man” (Read review)

Excerpt from Guardian review:

For Confidence Man, Haberman interviewed Trump three times. He confesses that he is drawn to her, like a moth to a flame.

“I love being with her,” he says. “She’s like my psychiatrist”.