Answer: skepticism; Humility.
Explanation:
Okay, let us fill in the gaps in the question given above;
''In psychology class, Paul claims that women are more empathic than men. If Anna asks, "How do you know?" she is demonstrating the scientific attitude of SKEPTICISM. If Paul immediately questioned his own statement, he would be demonstrating the scientific attitude of HUMILITY''.
PS: The two words in capital letters are the words to fill in the gap.
Okay, so let us define the meaning of skepticism. Skepticism is a kind of behaviour or attitude in which one doubt and question a fact or an idea. Looking at the question, we can see that Anna has a skeptical Behavior/attitude toward what Paul said asking him(Paul) how he knew that women are more empathic than men. This type of scientific attitude is known as skepticism.
Assuming Paul immediately questioned his own statement, Paul is said to be demonstrating the scientific attitude of HUMILITY, questioning your own belief.