SUO: Re: Physical and Abstract
Phil,
Yes. Photons are physical, according to the
first criterion: you can see them directly
if they are in the visible range, feel them
if they are in the infrared range, or detect
them indirectly by various instruments.
But as I said, the criteria for being abstract
include not being physical. Therefore, photons
are eliminated. Then I added some positive
criteria, such as being able to be transmitted
at the speed of light.
Negroponte had a good "sound bite" for making
the distinction: atoms vx. bits. If it's made
up of atoms, it's physical; if it's made up of
bits, it's abstract. However, he should have
generalized the term "atom" to include photons
and other subatomic particles.
But as I said before, I am not claiming that
my definition (or Negroponte's) exactly covers
all the cases that people commonly use in
ordinary language. That is why I put the caveat
in my KR book that the labels Physical and Abstract
are just mnemonic aids for my technical categories
P and A.
John
____________________________________________________________________________
> John,
>
> You wrote:
>
>> Besides not being physical (i.e., having negative
>> answers to the above questions), abstract entities
>> have affirmative answers to the following questions:
>>
>> 1. Can it have physical replicas, embodiments,
>> instances, encodings, or whatever similar
>> term you would prefer to use?
>>
>> 2. If you are given a physical replica of an abstraction
>> at one place and time, can you transmit it (the
>> abstraction, not the replica) at the speed of light
>> to another place and time where another physical
>> replica, sufficiently similar to the original by
>> whatever criteria you choose, can be reconstructed?
>
>
> The second criteria seems incorrectly worded, since only physical things
> (i.e. photons) can be transmitted at the speed of light from one place to
> another.
>
> Phil Jackson
>