The Value (and Risks) of Emulation

Courtesy of Evan Koblentz' recent mailing list message, behold this ancient analog computing device, Lego-style. The contrast between this device and the older reconstruction of the Babbage Difference Engine is illuminating. The latter aimed to be as faithful as possible to the original in terms of materials and design, in order to prove the viability of the machine within its original historical context.

This Lego Antikythera is instead an emulated piece of computing hardware; it looks nothing like the original and the gearing isn't even the same, to say nothing of the elegant Danish toys used to build it. From a historical perspective emulators like this serve a rather different role from reconstructions. They allow us to recapture some sense of what a historical device or piece of software was like, and how it was experienced and used, at relatively low expense. Of course, most emulators are created for reasons having nothing to do with historical interest, but that doesn't stop us form appropriating them to our own ends! The Computer History Museum has also been working to add more emulation to its historical repertoire, with plans for a web-based emulator of the IBM 1620.

Probably the richest vein of emulator development, however, has been in the field of video and computer gaming, where it allows enthusiasts to indulge their taste for older games that are not otherwise playable on contemporary machines, due to changes in hardware and/or operating systems. One especially fascinating example is the University of Illinois PLATO system. Some enterprising PLATO lovers have re-created that system in a lovingly-detailed emulator, which is used primarily to play multiplayer video games from the 1970s.

The subject of video game emulation takes me back to Nick Montfort and Ian Bogost's book Racing the Beam, which I discussed in my previous post, and to the risks of emulation. As Montfort and Bogost point out, it can be difficult to faithfully recreate the look of CRT graphics (especially vector graphics) on contemporary LCD screens; in other words, platforms matter.

One can imagine comparable examples from the history of computing broadly speaking, for example the difficulty of recreating the ergonomics and sensory experience of a teletype interface on a modern laptop. As we use emulators to help us better understand the past, we must also keep in mind the ways in which they distort our experience of it.