I think that almost everyone is slightly deluded.<p>The natural state of mind of healthy (i.e. not clinically depressed) people is to default to think that they are important and good at what they do. So you get things like 70% of drivers saying that they drive better than average. (And I saw a psychologist post somewhere online claiming that they had asked 500 people how good they were in bed, and exactly one person out of the 500 thought they were below average.)<p>At the level of subjective reality "I'm important" is obviously true in general, as you are presumably the most important person in your own life.<p>At the level of objective reality you have things like "you are one random individual among 8 billion, all of you living on a small rock on the outer edges of an insignificant galaxy, and the lifetime of the entire human species is hardly a blink of the eye in the timeframe of the Earth".<p>Although objective truth has the advantage of being objective, it is also somewhat depressing.<p>Terry Pratchett (of the Discworld series) has the concept of "knurd" ("drunk" spelled backwards). The idea is that people normally look at the world through rose-tinted glasses as if they were slightly drunk, being "knurd" is the state of being hyper-sober, stripped of all comforting illusions and seeing the world in all its harsh reality.<p>I certainly believe that this story is fairly close to being true, although I have no scientific studies to back it up :)<p>Although most people are slightly delusional, it may be more visible in people that are successful somehow somewhere, since they have an external story to collaborate the internal story: "I feel important, and this proves that I actually <i>am</i> important".<p>We also have hubris as one of the three virtues of a programmer ( <a href="http://en.wikipedia.org/wiki/Larry_Wall#Virtues_of_a_programmer" rel="nofollow">http://en.wikipedia.org/wiki/Larry_Wall#Virtues_of_a_program...</a> ), I have no reason to think that this is less true for entrepreneurs in general.<p>In short, I think a moderate amount of delusion is quite healthy, and possibly even essential :)