As stated, there is no dilemma. All the terms appear to be unqualified absolutes. Scientific theory is advanced through the longevity of it's proponents, and has nothing to do with the validity of the theory itself.
It means that (1) not to just trust scientists based on some kind of moral standing, (2) just because a scientist is sure that one thing is true and another thing is false doesn't necessarily mean the opposite is so, and (3) that science never finds "truth", but has models and theories that fit to reality to varying degrees.