LECTURE 5
BRADLEY, VAN INWAGEN AND
MOORE ON INTERNAL RELATIONS
VAN INWAGEN AND G. E. MOORE
GIVE DIFFERENT DEFINITIONS OF
“INTERNAL RELATION”
WE WILL CONSIDER THEM BOTH. IT SEEMS
DOUBTFUL THAT BRADLEY’S ARGUMENT
WORKS FOR EITHER ONE. (PERHAPS THERE IS
A DIFFERENT DEFINITION OF “INTERNAL
RELATION” FOR WHICH THE ARGUMENT
SUCCEEDS. WE JUST DON’T KNOW)
VAN INWAGEN’S DEFINITIONS
• A RELATION R WHICH MIGHT RELATE THINGS
X AND Y IS INTERNAL IF ITS’ HOLDING (OR
NOT) IS COMPLETELY DETERMINED BY THE
INTRINSIC ATTRIBUTES OF X AND Y.
• A RELATION R IS EXTERNAL IF AND ONLY IF
IT IS NOT INTERNAL.
EXAMPLES:
BEING THE SAME COLOR AS, BEING
LARGER THAN, BEING 10 FT. FROM
10 FT
BRADLEY’S “REGRESS” ARGUMENT
WE USE VAN INWAGEN’S RECONSTRUCTION OF
BRADLEY’S ARGUMENT THAT ALL RELATIONS ARE
INTERNAL (IN VAN INWAGEN’S SENSE).
SUPPOSE THAT X AND Y ARE RELATED BY AN
EXTERNAL RELATION R. WE WRITE THIS AS:
R(X,Y)
BRADLEY THINKS THAT THERE MUST BE SOME
EXPLANATION OF WHY R, X, AND Y ARE RELATED
IN THIS WAY.
CALL THE NEW RELATION R*
IF R(X,Y), THEN THERE IS A RELATION R* THAT
HOLDS BETWEEN R, X, AND Y, THAT MAKES
THIS SO: R*(R,X,Y). BUT R* CANNOT BE
INTERNAL; IT CANNOT BE DETERMINED BY
THE INTRINSIC PROPERTIES OF R, X, AND Y:
OTHERWISE R ITSELF WOULD BE INTERNAL.
BUT NOW WHAT EXPLAINS WHY THE
EXTERNAL RELATION R* HOLDS
BETWEEN R, X, AND Y?
CALL THE NEW RELATION R’
• IF R*(R,X,Y) IS TO BE EXPLAINED BY A RELATION R’
SUCH THAT R’(R*,R,X,Y), THEN R’ MUST BE AN
EXTERNAL RELATION. OTHERWISE R*
WOULD BE INTERNAL – WHICH WE HAVE
ALREADY RULED OUT. BUT NOW WE ARE
EMBARKED ON A VICIOUS INFINITE SERIES OF
EXTERNAL RELATIONS:
R,R*,R’,R”,… AND WE NEVER GET AN
EXPLANATION OF WHY R(X,Y).
WHAT’S THE POINT OF THIS
ARGUMENT?
IT IS SUPPOSED TO SHOW THAT THERE ARE NO
EXTERNAL RELATIONS. IT SEEMS TO
PRESUPPOSE THAT IF A RELATION IS NOT
INTERNAL, THEN THERE MUST BE SOME
“ADDITIONAL” EXPLANATION AS TO WHY IT
HOLDS. IT CAN’T JUST BE A “BRUTE FACT”
THAT EXTERNAL RELATIONS HOLD.
BRADLEY SEEMS TO THINK THAT THE
HOLDING OF INTERNAL RELATIONS HAS AN
EXPLANATION.
WE MIGHT JUST STOP WITH EXTERNAL
RELATIONS
THAT THE ONE SPOT IS 10’ FROM THE OTHER IS
JUST A FACT. “WHY” THE RELATION HOLDS
DOESN’T NEED OR HAVE A FURTHER
EXPLANATION. THIS SEEMS LIKE AN
ADEQUATE RESPONSE TO BRADLEY’S
ARGUMENT. IT SEEMS MUCH MORE SENSIBLE
THAN THE CONCLUSION THAT THERE IS ONLY
ONE THING.
G.E. MOORE GAVE A DIFFERENT
DEFINITION OF “INTERNAL RELATION”
G. E. MOORE 1873-1958
MOORE’S DEFINITIONS SIMPLIFIED
A PROPERTY P IS ESSENTIAL TO A THING A IF
AND ONLY IF A WOULD HAVE P IN EVERY
POSSIBLE WORLD IN WHICH IT EXISTED.
A RELATIONAL PROPERTY P IS
INTERNAL TO A THING A IF AND ONLY IF P IS
ESSENTIAL TO A.
MOORE POINTS OUT THAT IT IS
EXTREMELY IMPLAUSIBLE TO THINK
THAT ALL RELATIONAL PROPERTIES
ARE INTERNAL (IN HIS SENSE).
IF A IS TEN FEET FROM B, THEN IT DOES NOT
SEEM TO BE ESSENTIAL TO A THAT IT HAVE
THE RELATIONAL PROPERTY OF BEING TEN
FEET FROM B.
ON EITHER OF THESE WAYS OF
DEFINING ‘INTERNAL RELATION’, IT
SEEMS THAT THERE ARE EXTERNAL
RELATIONS
•MAYBE THERE IS MORE
THAN ONE SUBSTANTIAL
THING AFTER ALL!!