You have to be careful what you think you know.
Dr. King gave the "I have a dream" speech, not the "I have a plan" speech.
No one knows everything. But together, we know a whole lot.
Progress is more important than perfection.
To operate based on conviction and belief requires an acceptance that your actions could get you fired. This is different from pig-headed bravado, and it is different from putting the company at risk.
Pure pragmatism can't imagine a bold future. Pure idealism can't get anything done. It is the delicate blend of both that drives innovation.