John S. Bell: Subject and Object (1973).
by Miguel Mateo.
Bell’s paper is at a first glance a disaster. This can be safely stated. And, as all disastrous papers,
it may equally be a genial work or merely gibberish: hence we are in a case of (metaphorical)
quantum superposition, which will collapse into one of its (again metaphorical) quantum states
whenever observation takes place.1 Such observation, through our reading, will produce some
commentaries in the following lines.
Bell’s paper is a mess in a methodological sense, beginning with the fact that he states the aims
of the paper only at the end of it (“…following what seemed to be a minimal programme for restoring
objectivity…”), then due to the fact that he uses the word ‘beable’ in more than one context (and
perhaps thus with a different meaning each time), as noted by Ian Durham in Bell’s Theory of
Beables and the Concept of ‘Universe’ 2; as well as due to his carelessness in failing to define ‘beable’
properly rather than by example, and, also, by his process for the coinage of the neologism
‘beable’ itself, which is due to the particular ‘humility’ of the word.3 Then there is the fact of
the apparent lack of necessity in the scientific community for the introduction of such concept,
as stated by Bell himself: “The vagueness of the postulates in no way interferes with the miraculous accuracy
of the calculations.” This appears to leave unexplained the reason for writing this paper in the
first place.
But here ends the list of evidences of a possible identification of the work as gibberish (unless
we count as evidence our ignorance, the writer of this essay included, of the issues and
concepts of quantum physics in general). It is important, after noticing the above, to observe
that this paper was published within a book entitled ‘Speakable and unspeakable in quantum
mechanics’ 4. Therefore, it must be held in mind that the aim of the paper is firstly not about
stating new observations or new theories in the field, but about clearing up terminological
difficulties and ‘ambiguities’ that may be corrected.
If we refer to Bell’s ‘Beables for Quantum Field Theory’ (1988),5 we find a much clearer definition
of what beables are: “The beables of the theory are those elements which might correspond to elements of
According to the Copenhagen interpretation, at least. It may be useful to point out that in the classic exposition
of a system in quantum superposition, the thought experiment of Schrödinger’s cat, the odds before knowing
are 50%-50% for any of the ultimately becoming states, ‘alive’ or ‘dead’. In contrast, considering that the author,
Dr. Bell, was generally regarded by his peers as endowed with a genial intelligence, we see that there is at least
already a preexistent statistical tendency in his work to lean towards the ‘genial work’ state occurring, at the
expense of the probability of the ‘gibberish’ state occurring, when observed. To make a final judgment based
on this tendency already would be, however, to argue from authority.
2 Durham, I. (2018) Bell’s Theory of Beables and the Concept of ‘Universe’. Saint Anselm College: Manchester.
3 As stated in another one of his papers on the subject, to be cited below: ‘Beables for Quantum Field Theory’.
4 Bell, J. S. (1987) Speakable and Unspeakable in Quantum Mechanics. Cambridge University Press: Cambridge.
5 Bell, J. S. (1984) Beables for Quantum Field Theory. CERN Theoretical Department: Geneva.
1
reality, to things which exist. Their existence does not depend on ‘observation’. Indeed, observation and observers
must be made out of beables.” And, if we go to his ‘Theory of Local Beables’ (1975),6 we get the muchneeded clarification that beables are not metaphysical entities or about metaphysics at all, as
the -able suffix indicating possibility (and thus ‘possible worlds’) may imply. The idea behind
contrasting beables with observables is already present in Niels Bohr’s interpretation of
Schrödinger’s cat thought experiment, and merely consists in distinguishing that which we
observe through instrumental measurement from what there is actually out there, as we would
say, ‘for real’. Bell’s proposal is merely to draft a concept that encompasses such entities and
differentiates them from amongst the myriad observations, some of which are mere
abstractions and statistical tools (famously, Bohr did not regard the wave function as physically
real, for example). Bell’s aim with this is expressed through quoting Bohr in this
aforementioned 1975 article: “It is decisive to recognize that, however far the phenomena transcend the
scope of classical physical explanation, the account of all evidence must be expressed in classical physical terms”.
Bell seems to believe that bringing up the question of whether the specific objects studied by
quantum mechanics really do exist, or are merely abstractions, thinking tools and such kind of
ontologically unreal entities, will eventually be essential for unifying the theories of quantum
mechanics with the ‘classical’ (i.e: Newtonian) explanations, given that classical physics is
indeed about entities that can be said to exist, at least to a much less debatable degree,
independent of perception. In the end, the goal would perhaps be something akin to a
unification of physics, aiming ultimately to a general unification of the sciences. His idea is
ultimately a realist one: that physics explains actual entities in the world, beables, which are in
addition circumscribed to a local space (in the sense of a “limited space-time region”), and that it
is in terms of these that quantum mechanics is to ultimately be put.
Bell’s grapple with these related subjects of realism and localism, through his famous Theorem
(Bell’s inequality), is part of another subject, with which it would be improper, by its extension,
to deal here. It is also important to observe that Bell equally applies this concept of beables to
current theoretical situations in which the word ‘observable’ or ‘observation’ is instead used,
with a degree of success that requires a higher comprehension of the depths of physics to be
judged, than that of he who writes.
6
Bell, J. S. (1975) Theory of Local Beables. CERN Theoretical Department: Geneva.