A
PUZZLE
CONCERNING
MATTER
AND
FORM
Kit
Fine
Department
of
Philosophy,
NYU
Montgomery
Furth
has
written
1
,
"given
a
suitable
pair
of
individuals
...
there
is
no
reason
of
Aristotelian
metaphysics
why
the
very
fire
and
earth
that
this
noon
composes
Callias
and
distinguishes
him
from
Socrates
could
not,
by
a
set
of
utterly
curious
chances,
twenty
years
from
now
compose
Socrates
...".
He
does
not
specify
what
these
"curious
chances"
might
be.
But
we
may
suppose
that
Socrates
eats
Callias
for
his
lunch
and
that,
owing
to
the
superiority
of
Callias'
flesh
and
bone,
it
is
the
matter
of
this
which
remains
in
Socrates
after
the
period
of
twenty
years.
That
such
an
exchange
of
matter
is
possible
is
a
point
on
which
many
Aristotelian
scholars
could
agree.
However,
I
wish
to
argue
that
such
a
case
gives
rise
to
a
fundamental
difficulty;
for
its
possibility
runs
into
conflict
with
certain
basic
metaphysical
principles
which
are
commonly
attributed
to
him
and
which
would
also
be
commonly
accepted.
The
problem
consequently
arises
as
to
how
this
difficulty
is
to
be
resolved.
This
problem
itself
may
be
regarded
in
two
somewhat
different
lights.
On
the
one
hand,
it
may
be
regarded
as
a
difficulty
for
Aristotle.
The
question
then
is
whether
one
can
find
a
solution
which
would
be
acceptable
to
him,
either
in
the
sense
that
he
would
or
that
he
could
accept
it.
On
the
other
hand,
it
may
be
regarded
as
a
difficulty
for
a
neo-Aristotelian,
i.e.
to
someone
who
is
sympathetic
to
the
analysis
of
things
into
matter
and
form.
The
question
then
is
to
find
a
solution,
regardless
of
whether
or
not
it
would
be
acceptable
to
Aristotle.
For
the
most
part,
my
concern
has
been
with
the
exegetical
question;
and
even
here,
my
purposes
have
been
somewhat
limited.
For
I
have
not
attempted
to
settle
on
one
solution
as
opposed
to
another.
My
aim
has
been
to
map
out
the
exegetical
space
rather
than
to
locate
the
views
of
Aristotle
within
it.
However,
it
should
be
mentioned
that
I
count
myself
a
neo-Aristotelian
(and,
indeed,
it
was
my
own
commitment
to
hylomorphism
which
led
me
investigate
Aristotle'
views
in
the
first
place).
It
has
therefore
been
of
some
importance
for
me
to
take
the
purely
metaphysical
question
into
account.
The
Puzzle
.
Our
difficulty
is
simply
stated.
Suppose
that
Socrates
has
at
one
time
the
same
matter
as
Callias
has
at
another
time.
Then
their
matter
is
the
same;
their
form
is
the
same;
and
since
each
of
them
is
a
compound
of
matter
and
form,
they
themselves
are
the
same.
It
may
help
to
state
the
puzzle
in
more
formal
terms.
Let
us
use
S
for
Socrates
and
C
for
Callias.
Suppose
that,
in
the
envisaged
situation,
t
and
t'
are
the
respective
times
at
which
Socrates
and
Callias
are
assumed
to
have
the
same
matter.
Let
m
be
the
matter
of
Socrates
at
time
t
and
n
the
matter
of
Callias
at
time
t'.
Let
F
be
the
form
of
Socrates
and
G
the
form
of
Callias.
Given
some
matter
m
and
a
form
F,
let
Fm
(sometimes
also
written
as
F(m))
be
the
compound
of
m
and
F.
We
then
make
the
following
assumptions:
(1)
S
_
C;
(2)
m
=
n;
(3)
F
=
G;
(4)
S
=
Fm
and
C
=
Gn.
1
I
should
like
to
dedicate
this
paper
to
the
memory
of
Monty
Furth,
beloved
colleague
and
friend.
The
passage
cited
here
originally
appeared
in
his
[78],
p.643,
and
is
repeated
in
his
book
[88],
pp.
180-81.
I
should
like
to
thank
the
members
of
the
1989
conference
on
Aristotle
in
Oxford
and
of
the
1989
conference
on
predication
in
Irvine
for
many
helpful
remarks
on
the
topic
of
this
paper.
I
am
especially
indebted
to
Gavin
Lawrence
for
helpful
discussions
of
the
Greek
text.
The
two
puzzles
which
are
considered
here
were
originally
raised,
though
without
extensive
discussion,
in
my
unpublished
paper
Aristotle
on
Substance
(pp.
27-8).
(1)
says
that
Socrates
and
Callias
are
distinct,
(2)
that
Socates'
matter
(at
t)
is
the
same
as
Callias'
matter
(at
t'),
(3)
that
Socates'
form
is
the
same
as
Callias'
form,
and
(4)
that
Socrates
is
the
compound
of
his
matter
(at
t)
and
of
his
form
and
that,
likewise,
Callias
is
the
compound
of
his
matter
(at
t')
and
of
his
form.
All
of
these
assumptions
appear
to
be
reasonable;
and
yet
taken
together
they
yield
a
contradiction.
For
from
(2),
(3)
and
(4),
it
follows
by
two
applications
of
the
Leibniz's
Law
(the
substitutivity
of
identicals)
that
S
=
C,
in
contradiction
to
(1).
The
above
formulation
of
the
argument
has
the
advantage
of
brevity.
But
it
has
two
annoying
features.
The
first
of
these
is
that
the
assumptions
concern
a
specific
situation,
the
one
in
which
Socrates
eats
Callias.
This
makes
the
argument
needlessly
specific,
perhaps
dangerously
so;
for
we
run
the
risk
that
the
argument
may
not
hold
up
under
the
given
choice
of
a
situation,
even
though
it
would
have
held
up
under
some
other
choice.
One
might
try
to
avoid
this
difficulty
by
making
the
argument
suitably
general:
one
supposes
only
that
there
is
a
possible
situation
in
which
the
relevant
assumptions
hold.
However,
one
then
loses
the
ability
separately
to
assess
the
premises
upon
which
the
argument
depends,
since
the
assumption
of
several
specific
possibilities
has
been
replaced
by
that
of
a
single
general
possibility.
The
other
defect
in
the
formulation
is
that
it
presupposes
the
intelligibility
of
de
re
modal
discourse.
Thus
it
talks
of
the
possibilities
for
Socrates
and
for
Callias.
The
formulation
also
presupposes
the
legitimacy
of
the
application
of
Leibniz's
Law
within
modal
contexts.
Thus
it
is
assumed,
given
that
Socrates
and
Callias
are
the
same
in
the
given
possible
situation,
that
they
are
in
fact
the
same.
I
myself
would
not
question
these
presuppositions;
but
it
is
clearly
preferable
not
to
have
to
make
them.
Fortunately,
both
of
the
undesirable
aspects
of
the
argument
can
be
avoided
under
a
longer,
but
more
careful,
formulation.
This
has
three
premisses
which
correspond
to
the
premisses
(2),
(3)
and
(4)
in
the
short
form
of
the
argument.
Let
us
say
that
two
things
are
cospecific
if
they
are
of
the
same
lowest
species.
The
first
of
the
premisses
then
says:
Material
Migration
.
It
is
possible
for
two
cospecific
things
to
exchange
their
matter,
i.e.
for
the
matter
of
one
at
one
time
to
be
the
same
as
the
matter
of
the
other
at
another
time.
The
second
premiss
says:
Common
Form
.
It
is
necessary
that
any
two
cospecific
substances
have
the
same
form.
The
third
says:
Simple
Composition
.
It
is
necessary
that
anything
enmattered
is
the
compound
of
what
(at
any
time)
is
its
form
and
its
matter.
From
these
premisses
a
contradiction
then
follows
in
much
the
same
way
as
before.
It
should
be
clear
that
the
present
formulation
removes
the
defects
noted
above:
it
provides
an
analysis
of
the
assumptions
on
which
the
argument
rests;
and
it
avoids
all
appeal
to
de
re
modal
locutions.
Moreover,
the
present
version
of
the
argument
is
as
dialectially
cogent
as
the
earlier
version;
any
grounds
for
rejecting
its
premisses
will
be
equally
good
grounds
for
rejecting
the
other's
premisses.
We
will
therefore
adopt
the
long
form
as
our
official
version
of
the
argument,
although
we
will
usually
revert
to
the
short
form
for
purposes
of
exposition.
Equivocation
.
There
is
an
obvious
challenge
to
the
logic
of
the
argument,
which
is
that
it
equivocates
on
the
meaning
of
'matter'.
Perhaps
for
us
moderns
there
is
no
ambiguity
in
the
notion
of
the
matter
of
a
thing.
But
for
Aristotle,
matter
comes
in
"levels".
Thus
there
is
the
level
one,
or
proximate,
matter
of
something;
this
itself
may
have
proximate
matter,
which
is
then
level
two
matter
for
the
original
thing;
and
so
on.
Now
the
matter
of
which
Socrates
is
a
compound
is
his
proximate
matter,
while
the
matter
which
migrates
is
presumably
some
low
level
matter,
such
as
the
elements,
and
certainly
not
his
proximate
matter.
Indeed,
his
proximate
matter
is
his
body;
and
it
is
clearly
not
true,
in
the
envisaged
situation,
that
Socrates'
and
Callias'
body
are
the
same.
In
response
to
this
charge
of
equivocation,
it
should
be
pointed
out
that
it
is
not
evident
that
it
is
only
the
proximate
matter
of
something
which
combines
with
the
form
to
produce
the
corresponding
compound.
Suppose
Socrates
is
the
compound
Fm,
where
m
is
his
proximate
matter
(i.e.
his
body)
and
F
the
complementary
form;
and
suppose
m
is
the
compound
Gn,
where
n
is
the
proximate
matter
of
m
and
G
the
complementary
form.
Then
it
seems
natural
to
suppose
that
Socrates
is
also
the
compound
Hn,
where
H
is
some
sort
of
composition
FG
of
the
forms
F
and
G
2
.
So
it
seems
to
be
possible
in
principle
that
the
matter
of
which
Socrates
is,
in
part,
a
compound
should
be
the
same
as
the
matter
which
migrates
Unfortunately,
such
a
possibility
will
not
help
defuse
the
objection.
For
let
us
grant
that
Socrates
is
the
compound
of
some
low
level
matter
(such
as
fire
and
earth)
and
of
some
appropriate
compositional
form;
and
similarly
for
Callias.
The
componential
matter
will
then
be
the
same
as
the
migratory
matter.
However,
we
will
lack
the
same
reason
as
before
for
supposing
that
the
Socrates
and
Callias
have
the
same
compositional
form.
For
the
compositional
form
is
more
fine-grained
than
the
predominant
form
(i.e.
the
form
which
is
complementary
to
the
proximate
matter);
and
the
cospecificity
of
Socrates
and
Callias,
even
under
a
universal
conception
of
form,
will
be
insufficient
to
guarantee
that
the
compositional
form
is
the
same
3
.
Admittedly,
the
ambiguity
in
the
use
of
the
term
'matter'
will
disappear;
but
it
will
have
reappeared
as
an
ambiguity
in
the
use
of
the
term
'form'.
There
is,
however,
a
more
successful
way
in
which
the
charge
of
equivocation
may
be
resisted.
We
originally
described
our
possible
situation
in
such
a
way
that
it
was
meant
to
be
evident
that
Socrates
and
Callias
have
the
same
(predominant)
form.
We
must
now
redescribe
it
so
that
it
is
equally
evident
that
the
form
of
their
bodies
is
the
same,
and
so
on
all
the
way
through
the
different
levels
of
matter.
It
is
generally
unclear
when
the
matter
of
two
things
is
of
the
same
form,
even
when
the
things
themselves
are
of
the
same
form.
It
is
unclear,
for
example,
what
are
the
necessary
and
sufficient
conditions
for
two
human
bodies
to
be
of
the
same
form.
All
the
same,
there
is
a
very
general
sufficient
condition
which
may
be
given
for
two
things
to
be
of
the
same
form.
It
is
that
they
be
qualitatively
the
same,
i.e.
that
there
be
no
qualitative
differences
between
them,
either
of
a
relational
or
of
a
non-relational
sort.
For
surely
part
(perhaps
all)
of
what
is
implied
by
saying
that
the
form
is
univeral
is
that
it
can
be
specified
in
completely
general
terms,
i.e.
without
2
My
unpublished
paper
contains
an
attempt
to
develop
a
theory
of
compositional
forms.
It
should
be
noted
that
the
compositional
form
of
something
can
change
if
its
matter
changes.
For
suppose
that
F
is
the
form
of
x
and
that
m
=
Fn
is
the
matter
of
x
at
one
time
and
m'
=
F'n'
the
matter
of
x
at
another
time.
Then
the
corresponding
compositional
forms
of
x
at
those
times
are
FG
and
FG'.
3
Under
this
way
out,
we
must
allow
that
two
things
are
co-specific
even
though
their
proximate
matter
is
not;
the
co-specificity
of
Socrates
and
Callias,
for
example,
will
not
guarantee
that
their
bodies
are
co-specific.
For
if
Socrates
and
each
level
k
matter
M
k
of
Socrates
were
co-specific,
respectively,
with
Callias
and
each
level
k
matter
N
k
of
Callias,
then
presumably
the
predominant
form
F
1
and
each
level
k
form
F
k
of
Socrates
would
be
the
same
as
the
predominant
form
G
1
and
each
level
k
form
G
k
of
Callias.
But
then
the
compositional
form
F
1
F
2
...F
n
of
Socrates
would
be
the
same
as
the
corresponding
compositional
form
G
1
G
2
...G
n
of
Callias.
reference
to
any
particular
thing.
(This
might
also
be
thought
to
follow
from
the
requirement
that
form
be
definable).
Thus
we
may
guarantee
that
the
matters
of
Socrates
and
Callias
are
of
the
same
form
by
supposing
that
they
are
qualitatively
the
same.
Now,
in
general,
the
supposition
of
qualitative
sameness
will
require
that
the
universe
be
eternally
cyclic
(in
both
the
backward
and
forward
direction).
Socrates
and
Callias
will
then
be
counterparts
under
two
different
cycles.
However,
such
a
drastic
possibility
is
probably
not
required.
For
all
that
we
need
is
that
there
be
no
relevant
qualitative
difference
between
Socrates
and
Callias,
i.e.
no
qualitative
difference
which
is
relevant
to
them
or
their
matter
having
different
forms.
Of
course,
one
might
adopt
a
Leibnizian
view
on
form:
only
exact
qualitative
counterparts
have
the
same
form.
And
one
might
combine
this
with
a
Leibnizian
view
on
possibility;
no
two
things
can
be
exact
qualitative
counterparts.
The
possibility
of
Socrates
and
Callias
having
the
same
form
would
not
then
arise.
However,
Aristotle
would
not
have
adopted
such
an
extreme
position,
either
on
qualitative
form
or
on
the
existence
of
qualitative
counterparts;
and
so
he
would
not
have
had
comparable
reasons
for
rejecting
the
possibility.
Indeed,
even
if
he
were
to
reject
a
qualitative
criterion
for
the
sameness
of
form,
it
is
still
hard
to
believe,
given
that
it
is
possible
for
Socrates
and
Callias
to
have
the
same
form,
that
there
would
not
be
some
possible
situation
in
which
their
proximate
matter
also
had
the
same
form,
the
next-to-proximate
matter
had
the
same
form
(if
it
had
any
form
at
all),
and
so
on
all
the
way
down
to
the
penultimate
matter.
But
assuming
such
a
situation
is
possible,
whether
underwritten
by
a
general
qualitative
similarity
or
not,
the
puzzle
can
be
reinstated.
For
Socrates
and
Callias
are
distinct.
So
by
the
assumption,
their
(predominant)
form
is
the
same;
and
so,
by
Simple
Composition,
the
only
way
they
can
be
distinct
is
for
their
respective
proximate
matters
m
and
n
to
be
distinct.
Again,
by
the
assumption,
either
m
and
n
both
have
no
form
or
their
form
is
the
same.
In
the
latter
case,
the
only
way
for
m
and
n
to
be
distinct
is
for
their
proximate
matter
to
be
distinct.
Proceeding
in
this
way,
we
see
that
the
matters
of
Socrates
and
of
Callias
must
be
distinct
at
every
level.
But
also,
given
that
the
same
matter
cannot
exist
at
different
levels,
the
matters
of
Socrates
and
Callias
across
levels
must
be
distinct.
So
no
matter
at
any
level
of
the
one
is
identical
to
any
matter
at
any
level
of
the
other;
and
migration
is
again
ruled
out
4
.
In
this
reformulation,
it
can
be
supposed
that
the
componential
matter
is
proximate
matter,
as
long
as
Simple
Composition
is
taken
to
have
application,
not
only
to
sensible
things,
but
to
anything
enmattered.
Thus
Simple
Composition
becomes
the
assumption
that,
necessarily,
anything
enmattered
is
the
compound
of
its
form
and
its
proximate
matter.
On
the
other
hand,
4
In
a
rigorous
formulation
of
the
argument
we
could
substitute
a
notion
of
relevant
similarity
for
the
notion
of
co-specificity.
The
analogue
of
Common
Form
would
then
be:
necessarily,
relevantly
similar
things
have
a
common
predominant
form
(if
either
has
any
form
at
all).
It
must
also
be
assumed
that
the
proximate
matter
of
relevantly
similar
things
is
also
relevantly
similar.
It
may
be
noted
that
it
is
not
necessary
to
assume,
as
I
have
done,
that
the
matter
at
different
levels
in
Socrates
and
Callias
is
distinct.
For
let
m
i
be
the
matter
at
the
i-th
level
of
Socrates
at
the
one
time
and
n
i
the
matter
at
the
i-th
level
of
Callias
at
the
other
time.
Suppose
that
for
some
k
and
l,
k
<
l,
m
k
=
n
l
.
Since
m
k
and
n
k
are
relevantly
similar
and
since
n
k
has
something,
viz.
n
k+1
as
its
matter,
m
k
also
has
something,
viz.
m
k+1
,
as
its
matter.
But
then
m
k+1
is
the
matter
n
l+1
of
n
l;
and
the
argument
may
be
repeated
for
m
k+1
and
n
l+1
.
Proceeding
in
this
way,
we
see
that
there
must
be
an
infinite
descending
sequence
m
1
,
m
2
,
...
of
matters
of
Socrates,
contrary
to
the
well-foundedness
of
the
matter-of
relation.
we
may
allow
the
migratory
matter
to
be
non-proximate.
It
is
worth
noting,
however,
that
if
some
non-proximate
matter
migrates
in
the
envisaged
situation,
then
so
does
some
proximate
matter.
For
take
the
highest
level
at
which
the
matter
of
Socrates
migrates
to
Callias
(perhaps
this
is
the
level
below
that
of
flesh
and
bone).
Then
at
the
next
level
up,
we
will
have
two
distinct
things
between
which
there
is
the
migration
of
proximate
matter.
So
for
the
things
at
this
level,
something
like
our
original
formulation
of
the
puzzle
can
be
given,
with
the
componential
and
the
migratory
matter
both
now
being
proximate
matter.
Given
the
failure
to
fault
the
logic
of
the
argument,
let
us
turn
to
those
solutions
which
challenge
its
premisses.
There
are
three
such
solutions
in
all,
one
for
each
of
three
premisses.
Let
us
consider
each
in
turn.
Common
Form
.
The
common
form
assumption
states
that
it
is
necessary
that
co-specific
things
have
a
common
form
or,
under
the
more
refined
formulation,
that
it
is
necessary
that
relevantly
similar
things
have
a
common
form.
This
assumption
might,
of
course,
be
denied
on
the
grounds
that
forms
are
individual.
For
presumably,
in
that
case,
it
would
be
impossible
for
two
distinct
things
to
have
the
same
form
(even
it
were
possible
for
something
different
to
have
had
the
form
in
the
first
place).
It
is
not
my
intention
here
to
enter
into
the
debate
concerning
individual
form.
But
I
do
want
to
make
some
remarks
on
the
relevance
of
the
debate
to
the
resolution
of
the
puzzle.
It
should
be
noted,
in
the
first
place,
that
it
is
a
lot
easier
to
attribute
the
belief
in
individual
forms
to
Aristotle
than
to
hold
it
oneself.
For
Aristotle
seems
to
have
a
possible
basis
for
the
belief,
viz.
that
individual
forms
are
real
and
active
principles
in
the
world,
which
is
denied
to
any
right-
minded
modern.
Thus
in
the
absence
of
an
alternative
conception
of
individual
form,
the
neo
Aristotelian
must
find
some
other
solution
to
the
puzzle.
In
regard
to
the
exegetical
question,
it
should
be
observed
that
the
issue
of
whether
Aristotle
believed
in
the
mere
existence
of
individual
or
universal
forms
is
relatively
uninteresting.
For
granted
that
he
believed
in
universal
forms,
there
would
be
no
difficulty
in
supposing
that
he
believed
in
individual
forms
as
some
sort
of
indexed
version
of
the
universal
forms
(something
which
we
might
represent
as
an
ordered
pair
of
a
universal
form
and
a
thing
with
had
that
form);
and
given
that
he
believed
in
individual
forms,
there
would
be
no
difficulty
in
supposing
that
he
believed
in
universal
forms
as
some
sort
of
abstraction
from
individual
forms
(something
which
we
might
represent
as
an
appropriate
equivalence
class
of
individual
forms).
The
interesting
question
is
the
role
of
individual
and
universal
forms
in
his
thought
and
whether,
in
particular,
one
rather
than
the
other
is
to
be
accepted
as
the
"essence"
of
a
sensible
thing.
Similarly,
what
is
relevant
to
the
resolution
of
our
puzzle
is
not
the
existence
of
universal
or
individual
forms,
but
the
status
of
the
forms
which
enter
into
compounds.
Can
these
be
universal?
Or
must
they
be
individual?
The
philosopher
who
would
solve
our
puzzle
by
appeal
to
individual
forms
cannot
be
content
with
their
existence.
He
must
maintain
that
it
is
these
forms,
rather
than
their
universal
counterparts,
which
enter
into
a
compound;
and
this
can
only
be
maintained,
I
assume,
on
the
grounds
that
it
is
the
individual,
rather
than
the
universal,
forms
which
constitute
the
essence
of
things.
It
is
also
important
to
distinguish
between
a
partial
and
a
full
advocacy
of
individual
forms.
A
full
advocate
will
maintain
that
anything
with
a
form
has
an
individual
form
(which
serves
as
its
essence);
a
partial
advocate
will
maintain
that
this
is
only
true
for
some
of
the
things
with
form,
perhaps
for
all
living
things
or
for
all
things
which
need
not
themselves
be
the
matter
of
anything.
The
full
advocate
of
individual
forms
has
a
general
solution
to
the
puzzle.
But
the
partial
advocate
may
not;
for
there
may
be
applications
of
the
puzzle
to
some
of
the
things
which
he
concedes
are
without
individual
form.
Two
cases
are
of
special
interest.
The
first
is
that
in
which
certain
kinds
of
artifact
are
used
in
place
of
people.
Thus
it
may
be
that
one
ship
acquires
the
matter
of
another,
much
as
in
the
Ship
of
Theseus
puzzle
5
.
The
advocate
of
individual
forms
is
then
obliged
to
say
that
the
ships
have
their
own
individual
form
or
to
find
some
other
solution
to
the
puzzle.
Such
a
case
may
not
be
too
serious,
however,
for
someone
who
was
unwilling
to
extend
individual
form
to
artifacts;
for
he
could
always
dispute
that
the
matter
migrated
to
a
distinct
ship.
The
other
case
is
more
serious
in
this
regard.
For
as
we
have
observed,
if
the
low
level
non-proximate
matter
of
a
man
can
migrate,
then
the
proximate
matter
of
something
like
flesh
must
also
be
able
to
migrate;
and
hence
the
puzzle
can
be
restated
for
flesh
or
whatever.
In
such
a
case
the
advocate
of
individual
forms
cannot
dispute
migration.
So
he
must
either
dispute
Simple
Composition,
which
presumably
would
provide
him
with
an
alternative
general
solution
to
the
problem,
or
he
must
concede
that
flesh
and
the
like
have
individual
form.
Thus
it
seems
that
the
doctrine
of
individual
form
cannot
be
confined
to
substance,
i.e.
to
things
which
are
capable
of
existing
without
being
the
matter
of
something;
it
must
also
be
extended
to
matter,
i.e.
to
things
which
are
incapable
of
existing
except
as
the
matter
of
something.
We
should
note,
finally,
that
even
the
full
advocate
may
run
into
problems
if
he
regards
his
advocacy
of
individual
forms
as
a
way
of
saving
Simple
Composition.
For
as
we
shall
later
see,
there
is
another
puzzle
whose
resolution
would
seem
to
require
him
to
give
up
that
assumption.
Migration
.
Let
us
consider
whether
the
puzzle
might
be
solved
by
rejecting
Material
Migration.
It
is
clear
that
this
is
not
an
option
for
the
neo-Aristotelian,
for
there
seems
to
be
nothing
to
prevent
the
molecules
which
now
comprise
me
from
later
comprising
you.
But
whether
is
is
an
option
for
Aristotle
is
not
so
clear,
since
it
cannot
be
taken
for
granted
that
he
would
have
adopted
anything
like
our
modern
scientific
conception
of
matter.
If
form
is
taken
to
be
universal,
then
Migration
can
be
rendered
as
the
claim
that
it
is
possible
for
something
to
be
the
matter
of
two
distinct
things
with
the
same
form;
and
this
is
the
version
we
shall
use.
The
negation
of
Migration,
which
we
call
Entrapment
,
then
states
that,
necessarily,
things
with
the
same
matter
and
form
are
the
same.
______
It
is
important
to
distinguish
Entrapment
from
two
stronger
claims.
The
first
of
these,
which
we
may
call
Strong
Entrapment
,
says
that
things
with
the
same
matter
are
the
same.
Thus
Entrapment
does
not
allow
the
matter
of
anything
to
be
the
matter
of
anything
else
with
the
same
form,
while
Strong
Entrapment
prevents
it
being
the
matter
of
anything
else,
whether
or
not
the
form
is
the
same.
The
second
strengthening,
which
we
may
call
(Material)
Individuation,
says
that
two
things
of
the
same
form
are
the
same
in
virtue
of
their
matter
being
the
same.
Thus
Individuation
adds
to
Entrapment
the
requirement
that
the
identity
of
the
matter
should
be
5
It
is
worth
pointing
out
that
this
version
of
our
puzzle
is
not
the
same
as
the
Ship
of
the
Theseus
puzzle,
even
though
the
two
are
based
upon
similar
possibilities.
For
in
the
latter
case,
the
puzzle
concerns
a
conflict
in
our
criteria
for
identity
over
time;
whereas
in
our
own
case,
the
puzzle
concerns
a
conflict
between
our
intuitive
judgements
of
distinctness,
on
the
one
hand,
and
certain
principles
from
Aristotle's
hylomorphic
theory
of
substance,
on
the
other.
Thus
the
Ship
of
Theseus
poses
a
problem
for
anyone;
whereas
our
puzzle
only
poses
a
problem
for
the
adherent
of
hylomorphism.
Migration. Let us consider whether the puzzle might be
solved by rejecting Material Migration. It is clear that
this is not an option for the neo-Aristotelian, for there
seems to be nothing to prevent the molecules which now
comprise me from later comprising you. But whether is is an
option for Aristotle is not so clear, since it cannot be
taken for granted that he would have adopted anything like
our modern scientific conception of matter. If form is taken
to be universal, then Migration can be rendered as the claim
that it is possible for something to be the matter of two
distinct things with the same form; and this is the version
we shall use. The negation of Migration, which we call
Entrapment, then states that, necessarily, things with the
same matter and form are the same. It is important to
distinguish Entrapment from two stronger claims. The first
of these, which we may call Strong Entrapment, says that
things with the same matter are the same. Thus Entrapment
does not allow the matter of anything to be the matter of
anything else with the same form, while Strong Entrapment
prevents it being the matter of anything else, whether or
not the form is the same. The second strengthening, which we
may call (Material) Individuation, says that two things of
the same form are the same in virtue of their matter being
the same. Thus Individuation adds to Entrapment the
requirement that the identity of the matter should be
explanatory
of
the
identity
of
the
things
6
.
_
There
is
some
textual
evidence
which
seems
directly
to
support
the
view
that
Aristotle
held
to
some
form
of
Entrapment.
The
three
main
passages
are
from
the
Metaphysics,
viz.
Delta
6,
1016b,
31-32,
Zeta
9,
1034a,
5-8,
and
Iota
3,
1054b,
15-16.
Under
an
innocent
reading,
the
first
of
these
supports
Strong
Entrapment,
the
second
supports
Individuation,
and
the
third
supports
Entrapment.
Some
effort
has
gone
into
showing
that
the
support
for
Individuation,
or
even
some
form
of
Entrapment,
is
illusory.
I
myself
am
inclined
to
favour
the
innocent
readings.
I
am
also
inclined
to
think
that
Aristotle's
remarks
on
the
unificatory
role
of
form
in
Z17
and
H6
provide
some
indirect
support
for
Entrapment
7
.
However,
it
is
not
clear
to
me,
even
under
the
innocent
readings
and
with
the
indirect
support,
that
the
present
solution
remains
open
to
Aristotle.
This
is
partly
because
there
is
some
further
subtlety
in
how
Entrapment
is
to
interpreted.
If
the
puzzle
is
to
be
solved,
then
Entrapment
must
at
least
mean
either
that
the
proximate
matter
of
anything
enmattered
is
entrapped
or
that
the
proximate
or
non-proximate
matter
of
any
sensible
thing
is
entrapped.
But
the
above
passages
could
be
taken
to
support
the
restriction
of
Entrapment
to
the
the
higher
level
matter
of
sensible
things.
More
significantly,
there
is
the
possibility
that
Aristotle
is
guilty
of
an
inconsistency
on
this
point.
For
(as
I
will
later
propose)
he
might
believe
in
Entrapment
because
of
his
views
on
the
nature
of
unification
and
he
might
believe
in
Migration
because
of
his
views
on
the
nature
of
matter,
without
being
aware
of
the
inconsistency
between
the
two.
In
any
case,
we
need
to
consider
the
evidence
on
the
other
side,
in
favour
of
the
possibility
of
migration.
It
will
be
helpful
to
organize
the
consideration
of
this
question
around
certain
apparent
instances
of
migration.
We
shall
present
three
kinds
of
example
(in
order
of
increasing
cogency);
and
in
each
case,
we
shall
consider
whether
there
are
any
textual
or
intuitively
compelling
reasons
to
suppose
that
Aristotle
would
have
accepted
the
example.
But
before
so
doing,
let
us
make
some
general
remarks
on
how
the
examples
and
the
responses
to
them
are
to
be
characterized.
Any
apparent
case
of
migration
may
be
described
in
neutral
terms,
terms
to
which
both
the
opponent
and
the
proponent
of
Migration
can
agree.
Thus
they
will
agree
that
certain
things
continue
as
certain
other
things;
and
they
will
agree
as
to
the
6
.
There
is
also
a
principle
of
individuation
corresponding
to
Strong
Entrapment.
Moreover,
there
are
even
stronger
versions
of
Entrapment.
Thus
one
might
rule
out
the
possibility
that
the
matter
of
one
thing
could
ever
exist
except
as
the
matter
of
that
thing;
and
one
might
also
rule
out
the
possibility
that
part
of
the
matter
of
something
could
ever
be
part
of
the
matter
of
something
else
or
exist
except
as
part
of
the
matter
of
the
thing.
7
.
Charlton's
and
Cohen's
papers
examine
the
evidence
for
individuation.
The
remarks
on
unification
in
Z17
and
H6
will
be
discussed
later
in
the
paper;
and
Gill's
book
(p.
241)
presents
somewhat
different
considerations
in
favour
of
entrapment.
No
attempt
will
here
be
made
to
defend
the
innocent
readings.
But
let
us
briefly
consider
the
passage
from
Z9
in
which
Aristotle
writes:
"
And
when
we
have
the
whole
such
and
such
a
form
in
this
flesh
and
in
these
bones,
this
is
Callias
or
Socrates;
and
they
are
different
in
virtue
of
their
matter
(for
that
is
different),
but
the
same
in
form;
for
their
form
is
indivisible".
Some
commentators
(for
example,
Furth
in
his
book,
p.
180,
and
Anscombe
in
her
paper,
p.
94)
have
interpreted
this
passage
synchronically:
what
makes
Socrates
and
Callias
different
is
there
being
a
single
time
at
which
their
matter
is
different.
But
this
is
unsatisfactory.
For
the
passage
appears
to
be
a
response
to
the
Platonic
quandary:
given
that
Socrates
and
Callias
have
the
same
form,
then
what
makes
them
different?
An
adequate
interpretation
of
the
passage
should
therefore
make
it
read
as
a
reasonable
attempt
to
answer
the
quandary.
But
interpreted
synchronically,
the
passage
cannot
be
read
in
this
way,
since
it
fails
to
state
what
would
make
Socrates
and
Callias
different
in
the
case
in
which
there
is
no
common
time
at
which
they
exist.
Under
the
innocent
reading,
however,
the
difficulty
disappears;
for
what
makes
Socrates
and
Callias
different
is
that
the
matter
of
Socrates
at
any
time
at
which
he
exists
is
different
from
the
matter
of
Callias
at
any
time
at
which
he
exists.
This
is
therefore
a
strong
point
in
its
favour.
form
of
these
things.
But
they
will
differ
on
questions
of
identity.
The
proponent
of
Migration
will
hold
that
that
the
things,
as
described
in
the
case,
are
distinct
but
that
their
matters,
at
the
respective
times,
are
the
same.
The
opponent
must
hold
either
that
the
things
are
the
same
or
the
matters
distinct.
For
the
proponent
of
Migration,
the
prima
facie
evidence
for
the
claim
of
identity
is
the
existence
of
a
material
continuity
--
the
matter
of
the
one
particular
continues,
in
a
suitable
way,
as
the
matter
of
the
other;
and
the
prima
facie
evidence
for
the
claim
of
distinctness
is
the
existence
of
a
formal
discontinuity
--
the
form
of
the
one
particular
does
not
continue,
in
a
suitable
way,
as
the
form
of
the
other.
Thus
the
opponent
of
Migration
must
question
the
prima
facie
evidence
for
either
the
claim
of
identity
or
the
claim
of
distinctness.
In
the
one
case,
he
must
maintain
that
the
underlying
material
continuity
is
not
sufficient
to
convey
the
matter
from
the
one
particular
to
the
other;
somehow
the
matter
gets
trapped
on
the
way
(and
we
have
what
might
be
called
an
instance
of
entrapment).
In
the
other
case,
he
must
maintain
that
the
formal
discontinuity
is
not
sufficient
to
prevent
the
first
particular's
reappearance;
somehow
it
gets
reinstated
(and
we
have
what
might
be
called
an
instance
of
reinstatement).
Let
us
now
turn
to
the
examples
8
.
The
first
kind
arises
from
the
possibility
of
fission
and
fusion.
Fission
is
constituted
by
the
case
in
which
one
thing
of
a
given
form
changes
into
several
of
that
form,
fusion
by
the
case
in
which
several
things
of
a
given
form
change
into
one
thing
of
that
form.
Thus
both
are
cases
of
intra-formal
change;
the
"break"
in
the
form
consists,
not
in
its
being
different,
but
in
its
not
being
a
single
thing
which
continues
to
have
the
form.
It
seems
reasonable
to
suppose
that
fission
is
possible
just
in
case
fusion
is.
However,
combinations
of
the
two
seem
to
lead
to
instances
of
migration.
For
suppose
an
amoeba
xy
splits
into
the
amoebas
x
and
y,
which
then
fuse
back
into
the
amoeba
(xy).
Then
will
not
(xy)
be
a
distinct
particular
with
the
same
form
and
with
the
same
matter,
at
some
level,
as
xy?
The
opponent
of
Migration
could
deny
that
fission
and
fusion
are,
in
the
required
sense,
possible.
He
need
not
dispute
the
apparent
facts.
He
could
concede,
for
example,
that,
in
a
neutral
sense
of
the
term,
the
one
amoeba
continues
as
two.
But
he
could
deny
that
the
matter
persists,
i.e.
that
the
matter
of
the
two
is
the
same
as
the
matter
of
the
one.
The
appeal
to
entrapment
in
this
case,
though,
is
not
very
plausible
(and
as
we
shall
later
see,
may
not
even
help).
What
is
more
plausible
is
to
deny
that
the
final
amoeba
(xy)
is
different
from
the
first
xy.
The
matter,
at
some
appropriate
level,
remains
the
same,
but
so
does
the
amoeba;
and
hence
we
have
a
case
of
reinstatement
9
.
However,
other
apparent
cases
of
migration
which
arise
from
the
possibility
of
fission
and
fusion
are
not
so
readily
disposed
of.
We
are
inclined
to
think
that
something
can
survive
a
fission
or
a
fusion:
that
if
an
amoeba
Z
combines
with
a
sufficiently
small
or
insignificant
amoeba
then
the
resulting
amoeba
can
still
be
Z;
and
that
if
a
sufficiently
small
or
insignificant
amoeba
splits
off
from
an
amoeba
Z,
then
the
remaining
amoeba
can
still
be
Z.
But
the
opponent
of
Migration
is
unable
to
hold
such
a
view.
For
much
as
in
the
Ship
of
Theseus
case,
an
amoeba
Z
with
matter
M
may
split
into
a
large
and
small
amoeba,
surviving
as
the
large
part;
it
may
then
fuse
with
a
small
amoeba,
surviving
as
the
fusion;
and
so
on
until
the
resulting
amoeba
Z'
possesses
none
of
the
original
matter
M.
In
the
meantime,
the
small
8
The
framework
within
which
these
questions
have
been
considered
could
be
made
much
more
systematic
and
precise;
but
this
is
not
something
that
I
will
attempt
here.
9
It
is
interesting
to
note
that
in
this
case
we
have
the
migration
of
part
of
the
matter
to
a
distinct
thing
with
the
same
form
but
not
the
migration
of
the
whole
of
the
matter.
amoebas
that
it
has
shed
may
fuse
into
an
amoeba
Z''
whose
matter
is
M.
Our
opponent
is
then
required
to
make
Z
identical
with
Z',
on
account
of
its
survival,
and
also
to
make
Z
identical
with
Z''
on
account
of
their
common
matter
and
form.
It
therefore
appears
that
anyone
who
would
wish
to
solve
the
puzzle
by
denying
Migration
must
maintain
the
following
views
concerning
fission
and
fusion.
First,
the
matter
(at
some
level)
survives
these
processes.
Second,
the
things
themselves
do
not
survive,
no
matter
how
modest
the
change;
all
three
things
which
are
party
to
a
fission
or
a
fusion
must
be
distinct.
Third,
anything
which
ceases
to
exist
as
the
result
of
such
a
process
can
have
its
existence
restored
as
a
result
of
such
processes.
Thus
the
thing
is
not
completely
destroyed;
for
it
is
still
capable
of
existing.
And
the
processes
are
not
completely
destructive
in
their
effect;
for
what
they
destroy
they
can
also
restore.
A
similar
kind
of
case
arises
with
artifacts.
Suppose
that
a
house
is
wrecked
or
a
statue
melted
down.
Then
can
we
not
create
a
formally
identical
house