I was delighted to discover that someone is animating the talks and writings of C.S. Lewis on Youtube. If you’re not familiar with him, let me inform you that Lewis was a Christian apologist and an intellectual hero of the 20th century. He was a brilliant writer and is probably best known for a series of fantasy novels called the Chronicles of Narnia. But I most appreciate his work in fighting against the stupefying effects and baseless assumptions of postmodernism.
I highly recommend the first 9 minutes or so of the following video. In it Lewis begins to answer the question of whether it is morally right to fight in a war. In order to answer the question he lays out the process by which we discern what is right and wrong. And since part of that process is reasoning, you get “how to reason” thrown in for free.