Sometimes a question is the best response.
Answer: I am a true solipsist. (Gorgias)
Question: So why tell me?
A: There is no truth. (Gustave Flaubert)
Q: Is that true?
A: Knowledge is unknowable. (Francisco Sanches)
Q: How do you know?
A: It is irrational to assume that tomorrow will be anything like today. (David Hume)
Q: So you learned to speak, read, and write because…?
A: All cultures are equally valid. (Franz Boas)
Q: Including those that teach that all other cultures are invalid?
A: Truth is created, not discovered. (Friedrich Nietzsche)
Q: Did you just make that up?
A: There is no free will. (Baron d’Holbach)
Q: What makes you say that?