# Re: Symbol Systems

From: HARNAD Stevan (harnad@cogsci.soton.ac.uk)
Date: Wed May 29 1996 - 21:32:21 BST

> From: "Payne Ben" <bmgp195@soton.ac.uk>
> Date: Tue, 21 May 1996 12:51:43 GMT
>
> A symbol is a representation of an object, having a
> related meaning but without actually resembling or being
> causally connected to the object it stands for.

What is a representation? And what does "related meaning" mean?
(Remember, you are trying to explain to a kid-sibling who doesn't know
the answer already -- and can tell if he's not learning anything form
you!)

> One example of a system which uses such representations
> is language. Each language, whether it is is English,
> Chinese or Arabic, uses a system of letters and words as its
> symbols which have a set of syntatic rules and semantics.

Chinese has letters? Letters have syntax and semantics?

> By
> applying these rules, these representations can be
> interpreted in such a way as to give them meaning, which
> forms the basis for reading and writing, allowing people to
> communicate with eachother by using symbols.

Rule-based combinations of symbols can be interpreted as meaning
something; the words and sentences of a natural language are an example.

> Symbol systems are also used in mathematical
> applications, such as formulae for simultaneous equations or
> the equations of straight lines: y = mx + c. This does not
> actually mean anything on its own, but once it is applied to
> a set of numbers and values, it represents a specific
> object.

What are numbers and values? Aren't they just symbols too? Or do you
mean what the symbols STAND for? But then how do you "apply" symbols
to what they stand for? Don't you just apply symbol-manipulating rules
to symbols, and the RESULTS can be interpreted as standing for something?

> Also in maths, binary notation uses the symbols "0"
> and "1" to represent numbers. Once again, by applying the
> relevant rules, a sequence of "0"s and "1"s can be given
> some meaning.

How? This is a litte vague for a kid sibling: The point is that the
rules are simply formal ones: Things to do with 0's and 1's. The
remarkable thing is that those combinations of 0's and 1's (if you have
found the RIGHT rules, or algorithms) can give you systematic results,
and the results can be interpreted as meaning something. That is the
power of computation. It has reminded some people of the power of the
mind.

> In relation to computation and computers, symbol systems
> are used in computer programmes. A set of symbols is given
> as the input, which is then manipulated to give a symbolic
> output.

Computer programmes provide the rules for manipulating the symbols.
In that sense they are like big, long algorithms (they usually include
many algorithms within them).

> These symbols, when put together, are a
> representation of specific information which by themselves
> would mean nothing, but when interpreted in relation to the
> rules by which the computer reads them, they can be given
> some meaning.

How is this related to the Turing Machine? And the Symbol gorunding
Problem? (The connections need to be made, and made with understanding,
for an "A": Concepts are not isolated modules; they are interconnected,
and they form patterns, which you should star showing that you see.)

Not bad, though...

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