FORTUNE — “I’m not an expert at anything, including my own job,” Scott Adams writes in the introduction to How to Fail at Almost Everything and Still Win Big: Kind of the Story of My Life. “I draw like an inebriated howler monkey and my writing style falls somewhere between baffling and sophomoric. It’s an ongoing mystery to me why I keep getting paid.” He also notes upfront that “this is not an advice book. If you’ve ever taken advice from a cartoonist, chances are it didn’t end well.”
Breezily ignoring his own disclaimer, Adams goes on to pack the next 229 pages with contrarian career advice, based on the author’s mixed bag of experience in work and life. Although he told his mother when he was eight years old that he wanted to be the next Charles Schulz, Adams started his career in 1979 as a teller at a bank in San Francisco, where “my degree in economics made me somewhat overqualified for the job, and yet I still managed to be dreadful at it.” Altogether, he spent 16 years in corporate America, many of them in the middle rungs of financial management at Pacific Bell, and got an MBA from the Haas School at Berkeley.
Sounds pretty conventional, but Adams was a voracious autodidact. “I was a learning machine,” he writes. “If I thought something might someday be useful, I tried to grasp at least the basics.” Many of the observations in his book come from his delving deep into a seemingly random collection of subjects, from meditation and hypnosis to psychology, computer programming, and electronic game design.
Without letting go of his day job, and while drawing Dilbert strips at night, Adams patented an invention to make texting easier on old-style cell phones (smartphones made it obsolete), launched a line of veggie burritos called Dilberitos that sold in a few national chains before being crushed by the competition, invented some ill-fated computer games, and built several websites that went nowhere.
All of this is described in a chapter called “Some of My Many Failures in Summary Form” along with a few big, bad investments — including one in a predecessor to YouTube that flopped because Internet speeds were not yet fast enough for online video sharing to catch on. “This was about the time I started to understand that timing is often the biggest component of success,” he writes. “And since timing is hard to get right unless you are psychic, it makes sense to try different things until you get the timing right by luck.”
Trying lots of different things, while holding on to his day job, led him to come up with a formula: Every skill you acquire doubles your chances of success. Most people, he writes, are “better off being good at two complementary skills than being excellent at one … When I combined my meager business skills with my bad art skills and my fairly ordinary writing talent, the mixture was powerful.”
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Refreshingly for an autobiography by a rich and famous person, How to Fail at Almost Everything skewers the usual clichés about what leads to success. To take just one example, consider passion. Adams says successful people often cite passion as a reason for their rise because “everyone can be passionate about something or other … Passion feels very democratic. It’s the people’s talent, available to all. It’s also mostly bullshit.”
In his view, passion is a byproduct of succeeding at something, not a prerequisite to it. Looking back over the dozens of business ventures he started, or tried to start, he writes that he was passionate about each one until it fizzled. “The ones that didn’t work out — and that would be most of them — slowly drained my passion as they failed,” he writes. Drawing a comic strip “started out as just one of many get-rich schemes I was willing to try. When it started to look as if it might be a success, my passion for cartooning increased” — a lucky break for Dilbert fans.