People think of bipolar disorder as a bad thing. Well, maybe it would be an improvement over depression. No doubt I would jump at the chance to be irrationally happy about something. Writing a novel can be lonely, depressing work.
When you think about it, how does the human race go on without some mania in the mix? If everyone were completely logical, would they have taken the risks people took for air travel, space travel or jump rope? And what about enthusiasm? Isn't enthusiasm just a bit of hypomania anyway? For that matter, what about optimism?
I stipulate that sometimes we need some irrational hope or false optimism. A touch of mania here and there to keep us going when we have the urge to quit, to give us hope when things are down.
In fact, I further suggest that a degree of mania is required to be a starting writer. When you are a first time novelist, you know vaguely what the end product should look like; an idea turned into a book with beautiful sentences which people want to read. You don't know what the road to this goal will be like nor do you have any idea if anyone will actually want to read your book a-priori.
Consider that 95% of novels never make it to publication. It takes either a lot of conceit or a lot of self confidence to sit down, write a book, and think that anyone will want to read it. What is self confidence after all, but the rational self assurance, based upon previous achievement, that you have the skills to finish the job and finish it well. Any belief beyond that is irrational or should I say some kind of mania?
Does success have no other definition than to sell your novel? You work on this novel for a year or three, mostly without feedback. The grade is either pass or fail. You have a 5% chance of passing. Add to that the capricious nature of the publishing industry where good writing can be rejected and bad writing can be put upon a pedestal. Admit it, you have seen it!
So I say, you should be fitted for a straight jacket if you presume to set out to be a successful, published author.
Where does that leave us? Well, there is evidence which suggests that persistence, more than any other ability, produces successful authors. In the face of the odds, what is persistence here but an irrational belief that you will succeed. A mania, a faith, an unreasonable notion that you will produce a novel worthy of publication.