Discovery is a tricky thing.
You have probably had the experience of going to the garage to look for a pair of pliers and not being able to find them. A day or so later you discover that they were right there on the workbench all along, but you just didn't see them. Or you may have had the experience of trying to remember somebody's name, but no matter how hard you try, it just won't come to you. A few minutes after the person has gone, the name pops into your mind. As a student I sometimes had trouble understanding a concept in philosophy or theology.