in·con·vinc·ible /ˌɪnkənˈvɪn(t)səbəl/ (a.)無法使人信服的,難以說服人的
In·con·vin·ci·ble a. Not convincible; incapable of being convinced. None are so inconvincible as your half-witted people. --Gov. of the Tongue. ◄ ►