Act II, Scene 1

What Organs Do We Use to See?

Most people when asked what organs we use to see will answer “Our eyes” but this answer is far from complete. We use the word “see” in two ways — in the narrow visual sense and in the broader sense of “understand.” This is the first of several scenes that explore how we understand information in the broad sense. This scene explores the very narrow first visual sense. Your SWAG includes a pair of 3D anaglyph red-cyan glasses and a printed anaglyph which is also shown below.

The 3D glasses should be folded so that the red lens is in front of your left eye. Look at this anaglyph through the 3D glasses. You should be looking through the center of the anaglyph and you may need to move closer and further away until you get the full three-dimensional effect. Your brain has a constructed a 3D model of the Ingenuity helicopter on Mars. We see this 3D model using our eyes and our brains. The point of this scene is that our brains are, in fact, key organs as we see even in the narrow visual sense. Look at the two anaglyphs below through your 3D glasses to see two more examples.

Trees on a Foggy Day

Flowers

You can get a better appreciation of the essential part your brain plays in visually seeing a three-dimensional scene by looking at the two pairs of images below. For each pair the red image is the image your left eye sees and the cyan image is the one that your right eye sees.

Your brain has to do a lot of work to build 3D models from the two 2D images delivered to it by your two eyes.