"Believe those who are seeking the truth; doubt those who find it."
Andre Gide 20th century French author, Nobel Prize (Literature) winner
Think back in your career to all those who were certain about any number of things, or at least said they were.
How many turned out to be right?
Skepticism can be a good thing. Not to the point of doubting everything all the time, but as part of the process of validating what is and is not truth.