I was introduced to Dr. Callaghan at an art show opening in which I was one of numerous participants. He rather tersely said, "Come and see me sometime," and went off about his other duties. So after a week or two I went to see him. After a very cordial welcome, he (metaphorically) took me by the ear, led me to the office of the man in charge of the physical campus and said, in effect, "Buy something from this guy!" And left us together, both just a tad nonplussed.

The upshot was a commission for the gates, designs based on the interaction -- the interface -- between human cognition and digital computation.

Interface I

The upper and lower, repoussé panels of Interface I are based on cross-sectional micrographs of solid-state integrated circuit devices. The ring to which they're connected reiterates the appearance of a computer monitor that stands just out of the picture to the left and happens to have a round CRT screen and is intended to suggest the interface between the human perception and the digital representation of an object.

The object in the cross-hairs is a salvaged, polished brass toilet tank valve, proposing that even the most mundane of objects should be the subject of intentional and thoughtful design.

The hinges are equipped with tapered roller bearings. The axial line of the hinges is just a tad out of plumb so that the gates swing shut smoothly under their own weight after being opened but remain open if opened just past 90 degrees.

The ends of some of the connecting "wires" or "circuits" were left to protrude beyond the gate's frame to suggest lines of communication with the other gates or devices unspecified. As well, they function to act as stops so that the gates can't swing back into the narrow walkway behind. The director of the Center, whose office is visible behind the gate, soon complained of the irritating clanging sounds made when the gates closed so the projecting stops were retrofitted with black rubber crutch tips.

Interface II elaborates on the interaction of data, brain and representation. In the upper left panel is a rectangle of etched, 1/4" copper in a supporting frame which, overall, resembles the appearance of a microchip embedded inside the "package" you normally see on a circuit board.

The mind can conjure anything, from the infinitesimally small to the incomprehensibly large. We desire that our computing devices should be able to comprehend the same. The etched pattern on the copper "chip" is is a reference to the distribution of neutrinos in the universe -- the smallest known objects in the largest conceivable space. It is a burning question among cosmologists whether the distribution of neutrinos in the universe is smooth or lumpy. I opted here for "lumpy".

Interface II

The lower right panel is occupied by three neurons. There has been much controversy and heated dispute over the last fifty years over whether the mind is or is not essentially computational and over how mind arises from the intricacies of brain -- perceptrons, neural nets, neurocomputing, re-entrance, quantum phenomena and more.

No answer to all of that is offered here. But mind is surely an emergent property of those active, reticular structures of which neurons are the basic elements. Here the neurons are interacting in unspecified ways with notions of the submicroscopic and cosmic scales embraced by the copper "chip" and drawing pictures for the rest of us using a flatbed plotter, represented on the lower left.
In 1951, Warren McCulloch wrote [1]:

This brings us back to what I believe is the answer to the question: Why is the mind in the head? Because there, and only there, are hosts of possible connections to be formed as time and circumstance demand. Each new connection serves to set the stage for others yet to come and better fitted to adapt us to the world, for through the cortex pass the greatest inverse feedbacks whose function is the purposive life of the human intellect. The joy of creating ideals, new and eternal, in and of a world, old and temporal, robots have it not. For this my mother bore me.

Interface III

Interface III reiterates the image of the central solid state device radially connected to the world outside of it.

The upper and lower small, rectangular panels are etched with the name of the Center, my signature and date. On the reverse of the lower one, very small, is etched a tiny, smiling fish. I couldn't resist. It's the "fish" in "chips".

The copper panel sandwiched in the center is etched on the side shown with a mythical electronic circuit. On the reverse is etched a quotation from Warren S. McCulloch [2]:

What is a number, that a man may know it, and a man, that he may know a number?

[2] Warren S. McCulloch, "What Is a Number, that a Man May Know It, and a Man, that He May Know a Number?", (the Ninth Alfred Korzybski Memorial Lecture), General Semantics Bulletin, Lakeville, Conn: Institute of General Semantics, 1961). Republished in Embodiments of Mind, MIT Press, 1965.

Original photos by Peter Barss