They are liquid and air, mixed just so, producing a wonder of nature. They have outside skins that are so thin, it would take a hundred of them stacked together to equal the thickness of a sheet of paper. The small ones are as close to perfectly smooth and perfectly round as you will ever see in anything you can make with your hands.
Cheap entertainment? Yep.
A wonder of nature? You bet.
Their exquisite colors are revealed by the interference of the reflected light rays from the front and back sides of the film, a few millionths of an inch apart (what also causes the color patterns in opals, mother-of-pearl, drops of oil on a wet sidewalk, and some butterfly wings).
And they are playful things, insubstantial, beautiful. They come into being and then expire just seconds later; you can’t see them unless you are prepared to be very present in this moment. Mark Twain speculated on what value we would put on a soap bubble if there were only one in the world. I couldn’t afford it.