Prompt: Write a short story about a man who discovers a magical portal

John was a skeptic at best and a loner by nature. He had never believed in magic or the supernatural until one day, when he stumbled upon a door that led to a special kind of portal. The door led to a place where John could see the future. It was a powerful and scary experience and he quickly learned that if he ever told anyone about it, they would likely think he was crazy. John was determined to use the portal for his own purposes, but he was never able to find the courage to do so. Eventually, the portal closed and John was left alone with his own thoughts. He had discovered something powerful and mysterious, but he was never able to use it for what he intended.