Mostly politics, where I have learned to stop predicting anything that can't be directly seen -- especially the future. For example: 1. Trump wins. I firmly predicted the opposite. To be fair, most polls predicted the same. But the lesson is to be less certain about the future. 2. No chemical weapon found in Iraq. I firmly predicted the opposite. To be fair, when that event unfolded, it was not that long since the world had last seen Iraq actually use chemical weapons against Kurdish insurgents. But the lesson is to be less certain about anything that can't be directly seen.