"Take the first step in faith. You don't have to see the whole staircase, just take the first step."
Dr. Martin Luther King Jr. (1929-1968)
"If the path be beautiful, let us not ask where it leads"
Anatole France (1844-1924)
To the latter I would add '...but let us not tarry lest the path ahead lead to more spectacular views.'"The men who try to do something and fail are infinitely better than those who try to do nothing and succeed."
Possibly Martyn Lloyd Jones (1899-1981)