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Human Thought and the Design of Computers

Peter J. Denning wrote an excellent article titled "The Locality Principle" in the July 2005 issue of the Communications of the ACM. The article explained the story behind the locality of reference, a fundamental principle of computing with many applications. In a comment that appeared in the October issue of the same magazine I commented:

Peter J. Denning's "The Profession of IT" column ("The Locality Principle," July 2005) invoked an anthropomorphic explanation for the prevalence of the locality principle in computational systems, observing that humans gather the most useful objects close around them to minimize the time and work required for their use, and that we've transferred these behaviors into the computational systems we design.

A more intellectually satisfying explanation might be that we are dealing with two parallel and independent evolutionary design paths. Trading some expensive high-quality space (fast memory) in order to gain time performance is a sound engineering decision. It is therefore likely that evolution first adapted the human brain by endowing it with limited but versatile short-term memory and large long-term memory structure that exhibits behavior similar to caching.

Millennia later, we make similar design decisions when building computing systems.

The comment triggered an email exchange with Phillip G. Armour. It was one of the most intellectually satisfying email exchanges I've ever had, and I am reproducing it here, with his kind permission.

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MIT's $100 Laptop

The MIT Media Lab is working on a research initiative to develop a $100 laptop. This will be distributed through governments to schools to help the education of the world's students. These are my notes from a talk Michail Bletsas, Director of Computing at the MIT Media Lab gave on the subject, at an event organized by the Netmode Laboratory .

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Hard Disk Failure

I tell everybody that the question is not whether your hard drive will fail, but when it will fail. My laptop's drive started emmitting a loud grinding sound last Saturday.

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Creative Commons License Last update: Friday, June 16, 2017 6:36 pm
Unless otherwise expressly stated, all original material on this page created by Diomidis Spinellis is licensed under a Creative Commons Attribution-Share Alike 3.0 Greece License.