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Mental Floss Presents Forbidden Knowledge

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Think of anything bad, from art heists to Genghis Kahn, and it's likely to be included in this wickedly smart and humorous guide to the seedy underbelly of basically everything. The brainiac team at "mental_floss," creators of the hit magazine and last year's "Condensed Knowledge," have scoured the darkest, dirtiest corners of history and the globe to gather this ultimate collection of the bad stuff you're not supposed to know and you certainly never learned in school.Organized by theme, with chapters for each of the seven deadly sins, the book includes feuds, plagiarists, hoaxes, lies, schemes, scandals, evil dictators, mob bosses, acts of revenge, angry queens, cannibals and much more, all organized into bite-sized--albeit foul-tasting--lists (i.e."The Fascist Style Five Dictator Grooming Tips," "Four Biblical Girls Gone Wild" and "Three Delicious Animals We Charbroiled Into Extinction."). It's the perfect way to add some spice to a dull conversation and proves that learning can be not only easy, but exquisitely sinful.

320 pages, Kindle Edition

First published November 1, 2005

55 people are currently reading
1073 people want to read

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Will Pearson

18 books6 followers

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5 stars
255 (30%)
4 stars
324 (39%)
3 stars
207 (25%)
2 stars
36 (4%)
1 star
6 (<1%)
Displaying 1 - 30 of 47 reviews
Profile Image for Grayson.
174 reviews6 followers
October 17, 2012
This has some serious factual errors in it. I mean, really basic stuff -- I'm sorry, guys, but pepper was NOT used to mask the taste of spoiled food. Ugh. I gave up about 10% of the way through, during the incredibly inaccurate section on Christopher Columbus.
622 reviews2 followers
October 6, 2024
Weird format (chapters are the seven deadly sins) and really some weird subject matter.

Found it difficult to get through it, skimming quite a bit. By the time I reached to chapter titled sloth, I was experiencing some sloth myself, rushing through to get to the end.

I give it a 3 because it does have a lot of what I look for in this type of book.

Must say though - I have abandoned other Mental Floss reads as being just too wordy and difficult to slough through.
Profile Image for Jim.
3,102 reviews72 followers
September 11, 2018
Basically candy for the trivia set. Much I had already read about, but still many good and interesting tidbits, though honestly I cherry picked my way through the volume, as some subjects simply didn't interest me all that much. More than a few things to both make you smile, and also disgust. I like Mental Floss online. A nice diversion from the regular reading fare.
Profile Image for Ray Savarda.
482 reviews2 followers
July 5, 2019
Looked like it would be a good bathroom book - small, short stories on various topics.
After reading about 1/4 of it, found it not all that interesting, and moved on.
585 reviews
April 29, 2025
Gave up here within minutes. The writing was too cutesy and the structure disjointed.
Profile Image for Renee.
1,001 reviews
April 19, 2025
A decent trivia book based around the seven deadly sins. There are some factual errors and some of the writing feels of its time, but that happens in many trivia books.
Profile Image for Jonathan Lu.
360 reviews24 followers
July 31, 2013
As a sometimes reader of their magazine, figured I would be interested to pick this one up to learn some more random facts for my useless array of interesting info. Book began pretty blas�... dictators have weird mustaches and clothing, bands require weird demands for their contracts but not that witty or entertaining. Here's one I'll be sure to google... article published by Alan Sokal - "transgressing the boundaries: toward a transformative hermeneutics of quantum physics", which he wrote in order to demonstrate the ease at which a fake and meaningless article could be published without peer review and picked up by scientific journals.

In the chapter about sex, some great quotes... from Clark gable's wife - "god knows I love Clark, but he's the worst lay in town. If he had one inch less he'd be the queen of Hollywood." Wilt the Stilt - "If you look at it, you can say that I had so many women because I was such a bad lover, they never came back a second time." How did flirting go down during Victorian times? Evidently women had a complex system of signals using fans to communicate discreetly - touch right cheek = ok, left = not interested.

And who knew that the founder of Kellog cereal was a masturbation expert? Evidently he created cornflakes with the thought of how to get people to beat it less through improved diet. I'll have to pick up the bible again... evidently in chapter 18 of the first book of Samuel, it's written how Saul asked for the foreskins of 100 philistines from David in order to grant permission to marry his daughter. Expecting that David would die trying, he instead came back with 200 foreskins, and wedding bells rang.

What else did I learn about Russia? Evidently Rasputin had a 12" cock, and how he managed to remain in such control over Czar Nicolas was that Nick's wife was in love with him. And Catherine the great did not die of sex with a horse after all, but an aneurysm while shitting. Ok so there were far more chapters than just sex, but that's all I got.
Profile Image for Schnaucl.
993 reviews29 followers
October 30, 2007
It's an entertaining read, especially if you only have a few minutes here and there to do some reading. As with any book of this nature, if you know something about a subject before reading the book and they offer a different explanation you wonder about the accuracy of the rest of the information.

I've read in other places that the Spanish Flu started in America, not China, and the reason it was called the Spanish Flu was because their newspapers openly acknowledged it and the devastation it was causing in contrast to other countries where it was kept quiet so as to not lower morale. Mental_floss says that it's called the Spanish Flu because it hit Spain particularly hard.
Profile Image for Clare.
602 reviews9 followers
December 12, 2017
You will be smarter after reading this book. Your IQ score probably won't change but you'll be able to hold your own on some very interesting conversations.

Some of the facts contained here were surprising. Most were new to me, but some were not. In either case, The authors presented the facts in a new light and with humor.

This is a great read for someone who does not have time to sit down and read a full book at length. Instead you can pick up a chapter here or there and set it down for a couple weeks. When you return, you don't need to remember where you left off - each chapter can stand alone.

The book is equally as enjoyable as reading a Mental Floss magazine. Enjoy!
Profile Image for Sandra Strange.
2,678 reviews33 followers
August 25, 2013
This miscellany of historical topics covers R rated bits such as monarchs' sexual proclivities to national inferiority complexes and the wars they caused. The varied historical topics are organized according to the Medieval church's Seven Deadly Sins (Lust being one, thus the sexual stuff). It's all historical and tastefully presented, very informative and quite entertaining (but R rated just by its topics, but only in places, well labeled and easily skipped).
Profile Image for Ben.
587 reviews5 followers
November 11, 2015
Fun easy little 'trivia' book to read. Sound facts, though there is no citations (but mental_floss is a pretty good accredited source, so there might be only small trivial issues), it's easy to read, and light, basically a bathroom book. Broken down into the 7 deadly sins, it ranges the gambit from tiny and trivial interesting facts to large facts that we don't know (but probably should) to things like you know X but it's really Y. Overall fun book.
Profile Image for Kelley.
45 reviews6 followers
June 10, 2009
Another fun book from the folks at Mental Floss that want you to have fun while learning "new stuff". This time they take the theme of the Seven Deadly Sins and fill you in on the secrets of the world and people you may or may not have heard of.

History like this ignores the importance of dates and dead people, but this is Mozart once you have mastered the scales. Have fun.
Profile Image for Vanessa.
62 reviews
November 22, 2009
This is an awesome book for trivia junkies who love to pull out shockers at opportune times. It's split up in sections by topic (Lust, Greed, etc.), and each little portion is only 3-6 snippets. It's PERFECT for pre-slumber reading, where you want to get a little bit in, but prefer something not too heavy, that your half-asleep brain will be able to digest. I recommend!
Profile Image for Diana.
1,746 reviews
November 18, 2009
Bite sized lists of historical information are presented within the confines of the seven deadly sins.

A fun trivia book, even if the connections of the lists to the sins were sometimes extremely tenuous. I read this on the Kindle, so I'm not sure if the oddly inserted sidebars are a fault of the book or the conversion to digital format.
Profile Image for Pewterbreath.
515 reviews19 followers
February 8, 2010
This is one of those random facts books that is fun to kinda doodle through in the bathroom or while waiting for a bus or something. I don't think it's particularly significant, in the sense that you don't really LEARN anything, but it's an entertaining little fillip--and actually list books are quite addictive.
Profile Image for Albert.
18 reviews1 follower
December 11, 2007
This is a fun, lighter-than-air compendium of historical anecdotes, told in Mental Floss's signature pun-filled, mildly-snarky style. I'm a sucker for lists, especially lists of short, summary-style tidbits about bizarre stuff from history. So naturally, I enjoyed this immensely.
Profile Image for Jen.
603 reviews8 followers
March 30, 2011
I love trivia and it's my secret dream to go on Jeopardy someday, so this book was fascinating to me. However, I don't think that I would refer to all of these entries as "wicked." In fact, there were many where I didn't see the link to the chapter heading.
Profile Image for Answerblip.
1 review
June 12, 2009
This is a really funny book that has alot of great information and trivia questions. The cover of the book made me notice it, but whats inside got me hooked. I use this for parties and fun events to create games and fun times.

Answer Blip Trivia Team
http://www.answerblip.com/
537 reviews10 followers
December 21, 2010
Unfortunately the dedication "Mental Floss would like to thank the Devil for making a book about sins possible....and Voledemort. It's your inspiration that truly fills this book" was the wittiest most well written part of this book. Look for intelligent historical satire elsewhere
Profile Image for Katie.
191 reviews20 followers
December 27, 2010
Blurbs of history. Broken up by the Seven Deadly Sins. Interesting, but only a few paragraphs are written about each topic. Glossed over some of the topics. Definitely interesting for someone who wants "just the facts." Definitely loaded with trivia. Liked the Pride and Sloth sections best.
101 reviews2 followers
March 18, 2008
The format of the book is more than a little repetitive but it still contains many interesting bits of trivia.
Profile Image for Mike.
802 reviews7 followers
August 1, 2015
An excellent book for what it is. Short (three to four paragraph) entires about history, science, and pop culture.
Profile Image for Stacey.
971 reviews
January 12, 2010
Mental_Floss is awesome and I wonder how I didn't know about it until a year or so ago. A lot of these lists have appeared on the website (and kept me entertained over many a slow work day).
Displaying 1 - 30 of 47 reviews

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