Re: The Copy Paradox

Nick Bostrom (
Tue, 18 Nov 1997 23:08:41 +0000

John K Clark wrote:

> "Nick Bostrom" <> On Sun, 16 Nov 1997 Wrote:
> >"Mental state" is a bit ambigous.
> Bit yes ambiguous no. Unless the holly rollers turn out to be right the human
> brain must be equivalent to a Turing machine and the human mind equivalent to
> what a Turing machine does. What a Turing machine does is determined by the
> state it's in, and that depends on whether it sees a 0 or a 1 on a paper tape.
> How could anything be less ambiguous than that?

If the fundamental laws of physics turn out to be computable, then in
some sense *everything* must be equivalent to a Turing machine; this
would not mean, however, that there were no ambiguous terms. In
particular, there may be multiple correct ways of modelling the human
psyche on Turing machines, depending, e.g., on what level of
abstraction we assume.

> >I think the traditional line of thinking goes like this: The thought
> >"Mary loves John." involves the same concepts as "John loves Mary.",
> >namely the concepts "John", "loves" and "Mary". Nevertheless the two
> >thoughts are quite distinct.
> You're using the word "concept" in a somewhat more restrictive manner than I
> was, but that's OK.
> >rather than saying that you are a collection of concepts, you have
> >to say that you are a collection of conceps cum a structure defined
> >on that collection.
> If I use your implied definition of "concept" then I certainly agree.

Now, the point is that only according to this sense of "concept"
could they be said to be verbs, nouns, adjectives etc., as required
by your previous assertion that you are an adjective. If by "concept"
you meant "propositional thought", then if you were a collection of
such "concepts" you could obviously not be (a collection) of

> >And I don't think it makes literal sense to say that this collection
> >cum structure is an adjective -- it would be more correct to say
> >that it was a proposition.
> Perhaps, but the important point is that it's not a noun.

The point that it is not a noun is no more important than the point
that it is not an adjective or verb.

> >Moreover, in order to be a human being, it is not enough to be a
> >person.
> True but unimportant. The important part is the person, a human being is just
> a bag of protoplasm.

I was just noting that if we want to define what a human is it is
not enough to define what a person is.

> >One also has to belong to the human species, and whether one does so
> >presumably depends on one's ancestry and one's biological
> >constitution, not just on one's thoughts or concepts.
> What's so great about belonging to the human species? A human being is an
> animal so of course it must be biological, but the same is not true of a
> person.

You misunderstand me. My point was the same as the one you are
making, namely that it is possible to be a person without being
human. I wasn't saying anything about what's great and what isn't.

Nick Bostrom