Positive Thinking Is Powerful But Delusion Is Fatal You have to be optimistic to take on the challenges of entrepreneurship but you need to stay real to succeed at it.

I used to whine about everything as a kid. My dad used to call me a "chronic complainer," and he didn't mean it in an affectionate way, either. It really seemed to drive him nuts, but then, I think that was the idea. Just my own little way of getting attention from the big guy, I guess.

While we usually outgrow mechanisms that help us survive childhood, this particular one became a habit with me. Unfortunately, what worked like a charm in my dysfunctional Brooklyn family didn't go over so well in the adult world, by which I mean at work.

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One day as a young engineer, way back in the dark ages, my boss's boss -- a big, bald former college football lineman named Dick -- came over to my desk and just sort of stood there, looming over me. Feeling vaguely uncomfortable, I looked up and said, "Hey Dick, how you doing?"

"I'm doing great," he said, with a confident grin that made him look just like Mr. Clean, except without the earring and bushy eyebrows. Most of the managers at Texas Instruments were pretty upbeat guys, and while Dick didn't show a lot of emotion, he was more solid and grounded than anyone I'd ever met in my young life.

When he asked how I was doing, true to form, I took the opportunity to complain about something or other, but Dick wasn't taking the bait. He just sort of stood there, an imposing figure with a slight look of disapproval on his face. So I decided to try a different tact and asked how it was that he always seemed so optimistic.

Dick told me a story, how he long ago learned about the power of positive thinking and the positive effect it's had on his life. Sure enough, that resonated with me. After all, I was no dummy. Here I was, a clueless young engineer, and there he was, an impressive manager. Whatever helped him get from here to there, I wanted some.

That was a real turning point in my career. Make no mistake; I didn't shoot straight to the top. Careers are usually more like stock market charts -- lots of high frequency ups and downs while trending slowly upward over time -- and mine was no exception. But after that, I vowed to always be part of the solution, not the problem.

Don't get me wrong; I still complain. But there's a time and a place for everything, and it's called the privacy of your own home. There's simply no place for it at work, and that's a hard-line truth I hold to this day.

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Now, we can all go walking off into the sunset singing Kumbaya and call it a day, but that wouldn't be fair. Truth is, there's a downside to all that positivity. Taken too far, it can result in chronic denial of reality that's remarkably self-destructive. I've seen it time and again and the result is never pretty.

Over the years since those early engineering days in Dallas, I've had the distinct pleasure of working and competing with a veritable who's who of the high-tech industry. I've seen a few executives and business leaders succeed and I've seen many more fall by the wayside.

While there are many apparent reasons why businesses fail, if you look a little deeper, you'll usually find a delusional leader who chooses not to see the truth that's staring him right in the face. I've seen countless overly confident and overly optimistic CEOs drive their companies over a cliff.

If you over-indulge positive thinking, it leads to a dark side where the outcome is anything but positive. You can read countless scientific articles and studies on the subject, such as this one in Scientific American and this one in Psychology Today, but I can tell you that it's an enormous issue with all types of leaders and businesses.

Unfortunately, the problem has been greatly exacerbated by all the hype surrounding the controversial field of positive psychology. Throw in a growing cultural bias toward utopian thinking that's strongly reinforced by countless self-help books, inspirational blogs, social media content and self-proclaimed coaches, and you have a massive fad that's doing more harm than good.

Look, it's fine to be upbeat, but hiding behind rose-colored glasses is a very bad idea. Sweeping real issues under the rug instead of dealing with them has a name. It's called denial, and let me tell you, there are worse things than being a realist. Being delusional is definitely one of them.

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When the real world is telling you something that conflicts with your own beliefs, it's time to take a good hard look in the mirror and face what you see. Stay positive, but stay grounded. If you want to be successful over the long haul, keep it real, folks.