Looking at life in 3D

Last weekend, a friend of mine stayed over night at Pourtalès with me. The following morning, we decided to hit the Piste des Forts and take some pictures of the foliage before trees became bare. We made our way down the main trail, snapping photos of the "tunnel" of trees, the still green fields and elegantly lit leaves on the ground. We took one of the unpaved side trails that jutted out into the forest and captured some great shots around the various étangs. We eventually rejoined the main piste and made our way north to the little waterfall for a few for clicks. We'd now been out for about 2 hours and decided it was time to head back into town for lunch.

As we meandered our way back towards Robertsau on the piste, an old man astride a Vélohop stopped by us. Noticing the high-priced camera in my friend's hand, he demanded (in French), "Can I ask you a question?!"

My friend and I looked at each other in bewildered amusement and said, "Sure, why not?"

"When you take a picture with your camera there, and then print it into a photo, it's in 2D. But when you look at this same scene right here, right now, everything is in 3D! Why do you have to have a special machine to make 3D pictures?"

Puzzled, we scratched our heads. We postulated to him various theories. The concept of depth perception. The fact that our eyes are offset by a few inches creates 3D. None of these seems satisfactory to the old man.

"Why must you have complex machines for 3D pictures?! Why can your brain do it automatically?!" He seemed almost angry in his inquiry. We bantered back and forth for 5 minutes, yet nothing we said seemed to make the man happy.

Suddenly, a light bulb went off. I answered, "Because the human brain is the most complex, advanced computer ever created."

"That's right! Have a good day!" the man answered, and he peddled off on his way.