Fortunately, I can visualize in three-dimensions. I think any good field mapper can look at a map and see the Grand Canyon in three dimensions. You conceptualize, because you can’t see more than 30 or 40 feet under the ocean. So you must have a complete sense of reference. I don’t know whether that’s a gift, a compass that’s built into your brain, like a bird’s ability to migrate. I can know where north, south, east and west is at all times. I can remember where I was, and I can integrate it all in my mind. So when I go down there, I’m not lost. I’m very comfortable in total darkness with just a flashlight. It’s like working in the Rocky Mountains at night in a snowstorm from a helicopter with a spotlight. You can develop that skill. Certain people have that three-dimensional skill set.