“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
That said I do realize his goal is to find people thinking outside the box and not afraid to speak their mind, it’s just that he could have phrased it better.
Progress and truth are much, much more important than fitting in and pleasing others’ sense of propriety.
Scientific theories are merely our best approximations of how the world works.
Usually it is the anti-scientific drivel that is full of assertions and absolute statements, which is also what makes it so popular, especially among the less educated crowd.
I agree that making progress is of utmost importance, but the concept of truth is much more nuanced and, imo, difficult to define in objective terms.
1 sounds less arrogant than 2 IMHO and is what I would expect a scientific minded person to say. That makes it way simpler to discuss the actual reasons to believe X, without necessarily going against the individual who believes X.