If you find yourself in this situation, the best reaction is to simply mirror the “F” that has just been lobbed at you. “Fair?” you’d respond, pausing to let the word’s power do to them as it was intended to do to you. Follow that with a label: “It seems like you’re ready to provide the evidence that supports that,” which alludes to opening their books or otherwise handing over information that will either contradict their claim to fairness or give you more data to work with than you had previously. Right away, you declaw the attack.