The artist Danny Rozin has created “mirrors” that create shadow images of the viewer by actuating simple elements such as blocks or pegs.

Francis Crick was being coy when he titled his book “The astonishing hypothesis”: that all cognitive processes, including consciousness, are the product of neurons is much more than a hypothesis — it is a mature theory and a subject of active multidisciplinary investigation. The popularization of this insight may meet similar resistance as Darwin’s theory (although it may simply be lumped together with ‘Darwinism’). The view of consciousness as interaction of several mechanisms (or as Dan Dennett calls it, “a bag of tricks”) disagrees with the common sense notion of self as indivisible whole, the starting point in philosophical search (Cogito ergo sum). Therefore, all interesting philosophy of the next decades will be informed by recent experimental findings in neuroscience. Many authors are attempting to popularize the notions of neuronal nature of self. Others are taking advantage of the confusion to push a pet speculation or dogma.

Below I have compiled this chart with several books I have read that address questions of consciousness in intriguing ways. I rated these books based on how much new knowledge or insight they seemed to provide and whether these insights came by way of empirical findings or unfounded speculation. Click to enlarge.

Luckily, many popularizers of scientific understanding of mind and consciousness have made public presentations that are now available online. These make good previews of the contents of their books, and, if you have a couple of hours, getting to know these people will be time well spent.

Daniel Dennett:

Lectures on consciousness:

Jeff Hawkins, “On intelligence”

Christof Koch, “The Quest for Consciousness”

Recognizing self in the mirror is an established test of self-awareness. Humans and the great apes are alone in the animal kingdom to pass it.

We humans go a bit too far and insist on it, with embarrassing results:

I wonder how a mirror-trained bonobo would respond to this prank. How about a six-year-old child?

Randy Cooper uses copper mesh as his medium. The resulting figures appear somewhat like three-dimensional pencil drawings. Furthermore, the sculptures cast wispy shadows that often complement the overall composition.

Meshes are also an ideal medium for moiré synthesis. The moirés in this photo are probably an artifact of digital photography. However, the sculptures themselves can generate rich moiré patterns by interfering with themselves or their own shadows. The moirés could make the figures appear to move and shimmer as the viewer moves past them. Or, with a fair amount of craftsmanship, meaningful secret moiré patterns could be integrated in these figures visible only from a specific vantage point.

Originally uploaded by alwasaga

Another interesting property of shadow sculptures that can be exploited in computer-aided sculpting to enhance the visual surprise is that shadow shapes depend on the geometry of the surface onto which they are cast and the viewing angle.

I liked the artistic touch: the book appears to be a dictionary opened on imaginary and imagination.

In this piece by Kumi Yamashita titled Landscape, the shadow is cast by a straight edge and the shadow is shaped by the surface.

Another interesting property of shadows is that their meaning can change as the light source moves, even without resorting to moiré patterns, as in this sculpture by Markuz Raetz.

… or in this God-Ego duality shadow sculpture by Fred Eerdekens.

With the introduction of moiré effects, the number of possible distinct meaningful shadows can quickly multiply. So far, I have not seen anyone trying this medium.

Monstein moiré


I have just posted a video of a moiré pattern I generated earlier


The two gratings encrypt the images of Albert Einstein and Mona Lisa, hence Monstein. The two gratings are in green and purple — two opposite colors to combine into a gray image.