[DriveMaster]

All those comments have in common one thing: they are from people who claim that something can't be done, that others can't do/accomplish something.

Moral of the story: never claim that someone can't do something, no matter how unfeasible it might look. They might actually do it, and you will look silly.

[marksbren]

I agree that you should not immediately write off something, but there is definitely a need to lead/mentor people in the right way. When pg says, "I am worried..." he is doing the same thing as these quotes: expressing doubt.

That is what makes it so tough. As an entrepreneur you are hearing criticism often, sometimes it a super helpful and you need to change direction, other times it means you are onto something HUGE. It is difficult to decide which one it is.

[BerislavLopac]

Also known as the Clarke's first law... http://en.wikipedia.org/wiki/Clarke%27s_three_laws ;-)