1. Liberalism is about the power of ideas and knowledge, deployed widely.
All alternatives—Fascism and Communism and Monarchism and Theocracy—are about the power of people, of individuals, who need not have ideas more complicated than that the world should bow to them.
2. Good people protect and honor personal integrity because without it they have no sense of self, and become permanently lost. They do this first and foremost through honesty, through loyalty to, and respect for, the truth.
Bad people, having lost their core selves, lie to protect themselves from awareness of this loss.
These are approximate. It sounded better in my mind than written here, but I share anyway, with mild hesitation.