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Mirror Worlds: Or: The Day Software Puts the Universe in a Shoebox...How It Will Happen and What It Will Mean

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Technology doesn't flow smoothly; it's the big surprises that matter, and Yale computer expert David Gelernter sees one such giant leap right on the horizon. Today's small scale software programs are about to be joined by vast public software works that will revolutionize computing and
transform society as a whole. One such vast program is the "Mirror World."
Imagine looking at your computer screen and seeing reality--an image of your city, for instance, complete with moving traffic patterns, or a picture that sketches the state of an entire far-flung corporation at this second. These representations are called Mirror Worlds, and according to
Gelernter they will soon be available to everyone. Mirror Worlds are high-tech voodoo by interacting with the images, you interact with reality. Indeed, Mirror Worlds will revolutionize the use of computers, transforming them from (mere) handy tools to crystal balls which will allow us to
see the world more vividly and see into it more deeply. Reality will be replaced gradually, piece-by-piece, by a software imitation; we will live inside the imitation; and the surprising thing is--this will be a great humanistic advance. We gain control over our world, plus a huge new measure of
insight and vision.
In this fascinating book--part speculation, part explanation--Gelernter takes us on a tour of the computer technology of the near future. Mirror Worlds, he contends, will allow us to explore the world in unprecedented depth and detail without ever changing out of our pajamas. A hospital
administrator might wander through an entire medical complex via a desktop computer. Any citizen might explore the performance of the local schools, chat electronically with teachers and other Mirror World visitors, plant software agents to report back on interesting topics; decide to run for the
local school board, hire a campaign manager, and conduct the better part of the campaign itself--all by interacting with the Mirror World.
Gelernter doesn't just speculate about how this amazing new software will be used--he shows us how it will be made, explaining carefully and in detail how to build a Mirror World using technology already available. We learn about "disembodied machines," "trellises," "ensembles," and other
computer components which sound obscure, but which Gelernter explains using familiar metaphors and terms. (He tells us that a Mirror World is a microcosm just like a Japanese garden or a Gothic cathedral, and that a computer program is translated by the computer in the same way a symphony is
translated by a violinist into music.)
Mirror Worlds offers a lucid and humanistic account of the coming software revolution, told by a computer scientist at the cutting edge of his field.

237 pages, Hardcover

First published January 1, 1991

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About the author

David Gelernter

33 books65 followers
Librarian Note: There is more than one author by this name in the Goodreads database.

David Hillel Gelernter (born March 5, 1955) is an artist, writer, and professor of computer science at Yale University. He is a former national fellow at the American Enterprise Institute and senior fellow in Jewish thought at the Shalem Center, and sat on the National Endowment for the Arts. He publishes widely; his work has appeared in the Wall Street Journal, New York Post, LA Times, Weekly Standard, Frankfurter Allgemeine Zeitung, and elsewhere. His paintings have been exhibited in New Haven and Manhattan.

He is known for contributions to parallel computation and for books on topics including computed worlds ("Mirror Worlds"), and what he sees as the destructive influence of liberal academia on American society, expressed most recently in his book America-Lite: How Imperial Academia Dismantled Our Culture (and Ushered in the Obamacrats).

In 1993 he was sent a mail bomb in the post by Ted Kaczynski, known as the Unabomber, which almost killed him and left him with some permanent disabilities: he lost the use of his right hand and his right eye was permanently damaged.

(From Wikipedia)

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Displaying 1 - 13 of 13 reviews
Profile Image for Jessica.
266 reviews12 followers
April 13, 2015
Gelernter definitely had a vision of the world to come, and I think he figured a lot out. It's just too bad he's such a jerk, and has to speak in a constant stream of metaphor and make up stupid names for things instead of calling them by their real names. Simultaneously condescending and patronizing. Ugh. But thought-provoking nevertheless
Profile Image for Sloan.
55 reviews16 followers
July 8, 2022
An interesting look into a possible future of computing with just a small hint at the social implications. Written in 1991, it did a pretty good job of describing a large chunk of what computing is like in the 2020's. Distributed computing, data streaming, pub/sub messaging, ephemeral machines, social networking. All of this is described, but in a way that is trying to relate to a physical system in order to paint a picture of each layer that builds a Mirror World.

Not everything is on the mark and we are still not quite near the fidelity or real-time scale described from Gelernter, but we are awfully close. The current interest in a 'metaverse' as a sort of virtual social space explored visually is even closer to Gelernter's Mirror World.


The software model of your city, once it's set up, will be available (like a public park) to however many people are interested, hundreds or thousands or millions at the same time. It will show each visitor exactly what he wants to see it will sustain a million different views, a million different focuses on the same city simultaneously. Each visitor will zoom in and pan around and roam through the model as he chooses, at whatever pace and level of detail he likes. On departing, he will leave a bevy of software alter-egos behind, to keep tabs on whatever interests him. Perhaps most important, the software model can remember its own history in perfect detail; and can reminisce pointedly whenever it is asked. And everything is up to date, to the millisecond.


While the overall idea of a virtual representation of a real world space probably wasn't even a new idea in 1991, it's the depth Gelernter explores in the creation of these Mirror Worlds that is interesting. The clarity of the process of how each layer of a Mirror World is built is rather impressive.

This is a man that knows exactly what he's talking about but tries to explain it in as close to non-technical terms as he can get. However, I don't believe that folks without a software or computing background would fully grasp the concepts. Even the physical abstractions used may confuse the average that doesn't really understand how systems are constructed or even more so - doesn't care.

During this whole process of explaining how to build each layer of a Mirror World, it is assumed that this would bring about incredible benefits for everyone. It is only in the last chapter where there is a discussion about the potential negatives that may arise. These are no mere small inconveniences.

I found the portion about technology bringing about a new form of serfdom compelling as this is something we are seeing in real time in the 2020's. We have seen amazing technology that once empowered and connected us being used to divide and control us. We became dependent and complacent and now we are on the path of getting what we deserve. A brave new world, indeed.


"If you shut off your TV, who cares?" Ed says. "Who steals my Tube steals trash. But if you shut off your Mirror World in a fit of pique, you really are less well-informed than the other guy. There's really no way you can know as much about a Mirror Worlded reality if you don't watch the Mirror World. And that's a recipe for real dependence. The guys who run these operations are like TV and they're not: because they don't just control entertainment. They control reality. Do you smell a fault?



Another chunk that I liked from earlier in the book.

Nowadays, everything seems to be subtly and mysteriously connected to everything else. To build a dam, review a hospital's rates or set American trade policy you must pick your way over a vast sticky web (of laws, interest groups, technical problems) anchored in far-flung outlandish places. The big picture is a cypher. The whole is simply too complicated to comprehend.

Can we afford to go on this way? Who will accept responsibility for our ultimate achievement, the Incomprehensible Society? Is ant mindedness our fate? What are we going to do about it?



You may also like:
Future Shock
For more predictions of the future - quite fun!

Systems Thinking: Managing Chaos and Complexity - A Platform for Designing Business Architecture
This is a large book and covers a lot of ground, maybe too much. However, if one wants to understand how to think more holistically about systems of all sorts it could be a great resource.

Designing Data-Intensive Applications
If you are interested in distributed systems, this is great overview.
Author 4 books7 followers
January 4, 2018
Good book for getting a narrative feel for what programming is about; great discussion / think book as it was predictive and so it gives us a way to step outside much of what we use technologically right now and realize it didn't necessarily have to be this way, these are constructs created by people not inherent to computer culture. Epilogue is much of what the book is best for. Younger students will have a hard time following the book, though -- as did I at many points.
Profile Image for J M.
6 reviews
April 8, 2024
A cool way to describe google maps and the journey we are on into the realm of mirror worlds. It is a good book to get inspiration and understanding from. I definitely glossed over some of the drier intricate sections.
13 reviews
March 2, 2014
A bit of a yawner to quite honest.

The thesis that the real world would be duplicated/overlaid/represented in cyberspace was pretty obvious even at the time, although the literal, almost VR, picture Gelernter painted seems, and seemed, a little unrealistic.
Much of the capability has been realised instead as a fragmented montage at varying levels of abstraction rather than an integrated virtual world.
I can't yet fire up google earth, fly over the central bank, and click to find out current interest rates, M1, etc, or fly over the airport to see recent arrivals and last minute flight deals, and then click to book one of them, which is pretty much the picture Gelernter painted.
But I can fly over the airport in google earth to see the buildings.
I can visit a flight bookings site to grab a last minute deal.
I can view real-time traffic data overlaid on a map,
So unsurprisingly, the essence, if not the character, of the vision has ripened.

More prescient, or at least less obvious, was Gelernter's idea of a "lifestream", whereby everything you view or create is organised as a timeline rather than filesystem folders or whatever. That is still a work in progress, but is gradually being recognised as a pretty good way to organise things.
Profile Image for Olga Werby.
Author 24 books189 followers
September 23, 2015
David Gelernter’s visionary, although dated, book, “Mirror Worlds: or the Day Software Puts the Universe in a Shoebox…How It Will Happen and What It Will Mean,” is a must for science fiction fans as well as product interaction designers. Dr. Gelernter thinks big and comes up with a futuristic model of computers embedded in the very fabric of society. The book was written in 1993, and he has published a few books since then, but for scope of technological futurisms, this one is my favorite.
Profile Image for Aaron Kent.
258 reviews7 followers
November 27, 2011
This book, published in around 1991 is wonderful for what it gets right and doesn't predict. It still feels really relevant as a simple primer for the internet as it's impacted by data-structures and some kind of AI. The Epilogue is worth the read alone.
Profile Image for Karolis.
40 reviews9 followers
January 9, 2014
Interesting ideas, and very much ahead of their time. I didn't really enjoy the tone of the author but I'd still recommend reading this book. It fits well as a primer for what we're seeing software starting to achieve, slowly: the idea of top sight is very alluring .
Profile Image for Brendan .
780 reviews37 followers
August 28, 2007
The Unabomber didn't like it ~ sent this guy a bomb
Profile Image for Lee T..
41 reviews4 followers
January 4, 2010
Started strong but dragged in the middle as it is a bit dated.
Profile Image for 'Jj.
60 reviews10 followers
August 24, 2012
I think it was this book more than anything else that lead Ted Kaczynski to target Gelernter
Profile Image for Dave.
429 reviews18 followers
May 2, 2015
This book had a profound influence on my life.
Displaying 1 - 13 of 13 reviews

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