A friend confided in me that he is constantly overwhelmed by seeing all possible outcomes of daily events?

Some people's brains are just "wired" a little differently. Some can perform amazing mathematical calculations, some see sounds as colors, and so on. It sounds like he has an unusual grasp of cause and effect. I wouldn't call him psychic, because seeing all possible outcomes isn't the same as seeing the future. No offense to your friend, but it sounds like a mild form of obsessive-compulsive disorder. He seems to be compelled to follow everything he reads to its logical conclusion. It's not necessarily a bad thing as long as it doesn't interfere with his daily life. Maybe, like the fictional detective Monk, he could find a way to put it to good use. He might be successful as an actuary for instance, or in some other field dealing with risk and possible outcomes.