Excerpted from here:
If they tell you to quit, compare their reasons. If the reasons are similar, and all of the counselors have had successes in the field, take them seriously. Think through their reasons. Do they make sense?
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Is a problem worth solving if no one but you ever recognizes that it has been solved? If not, limit your commitment.
If you have to fund it yourself, why do you think anyone will pay you back? Who, How Much?
If you were to be remembered for only one thing, is this project the thing you would choose? Will they remember your failure? If so, it’s a very big project. Be prepared.
If it isn’t completed, will anyone’s life be significantly worse off, other than yours?
If you don’t do it, who can? Will he? If he doesn’t, would this be bad for the world?
Has it been attempted before? If so, what killed it?
Is it so important that if your worst enemy pulled it off, would you still be glad the project was completed?
Would you still do it if there were no monetary payoff? I have a project like this.