Dream lofty dreams, and as you dream, so you shall become. Your vision is the promise of what you shall one day be; your ideal is the prophecy of what you shall at last unveil.
If I started worrying about how my constituents are going to react to every move I make, I wouldn't be able to do my job here. I'll do what I think is right and explain it later.
Today's preoccupation with physical theories of everything takes a wrong turn from the purpose of science - to question all things relentlessly. Modern physics has become like Swift's kingdom of Laputa, flying absurdly on an island above the earth and indifferent to what is beneath.