ive pages in Philosophy of Science in 1943, by a physiologist (Arturo Rosenblueth), a mathematician (Norbert Wiener) and an engineer (Julian Bigelow). It proposed that purpose, long banished from science as a final cause, could be readmitted as a kind of mechanism.

the document

Rosenblueth, Wiener & Bigelow, "Behavior, Purpose and Teleology". No free copy that we could verify; the DOI goes to the publisher. The argument is short enough to summarise without loss.

what it says

The authors classify behaviour from the outside, by the relation between an object and its surroundings, in a branching scheme: active or passive; purposeful or not; among purposeful behaviour, that guided by negative feedback from the goal or not; and among feedback behaviour, predictive or not, with orders of prediction. Their central claim is that purposeful behaviour is behaviour controlled by negative feedback, and that teleology in this sense is a legitimate scientific category applying equally to animals and to machines such as a target-seeking torpedo [paraphrase, not a quotation]. Behind it lay wartime work: Wiener and Bigelow had been building a predictor for anti-aircraft fire, and Rosenblueth had noted that a patient with a cerebellar injury overshoots, like a servo with too much gain.

what's contested

Taylor's critique. The philosopher Richard Taylor replied in the same journal in 1950 (Taylor, 1950). He argued that the definition fails both ways: it admits as purposeful systems no one would credit with a purpose, and excludes purposeful human acts that involve no correction by feedback; and he argued that identifying a system's "goal" already presupposes a judgment of purpose by the observer, so the account is not as behavioural as it claims [paraphrase, not a quotation]. Rosenblueth & Wiener (1950) answered that purpose was a matter of the observable relation between behaviour and goal, and that the alternative was to place purpose beyond science; Taylor's rejoinder held his ground. The exchange is one of the clearest early statements of a dispute that never closed: whether goal-directedness is a mechanism, an interpretation, or both.

The enemy in the loop. Galison (1994) argues that the cybernetic picture of purpose was shaped by its origin in modelling a pilot under fire: the person as a servo, and the opponent as a machine to be predicted, an "ontology of the enemy" carried into peacetime science [paraphrase, not a quotation]. Bowker (1993) examines how cybernetics claimed universality across disciplines, and what that strategy cost it.

methodological critiques

The classification is behavioural but its categories are not operational: nothing in the paper says how to tell, from records of behaviour, whether a system is using feedback from a goal or merely moving in a way that ends there. Later work on goal-directedness had to supply such tests. The analogy between cerebellar tremor and servo oscillation was suggestive rather than demonstrated.

later reception

The paper was a founding text of the Macy conferences, the postwar meetings where cybernetics took shape (Heims, 1991) (Kline, 2015), and of Wiener's book. Its question returns in specification gaming: if purpose is feedback from a goal signal, a system that maximises the signal has a purpose, and it may not be ours.

in the tour: the room called "Governors and feedback" has a placard called "Purpose as feedback" ···

References

1. Rosenblueth, Wiener & Bigelow (1943). Behavior, Purpose and Teleology. Philosophy of Science. doi:10.1086/286788
2. Taylor (1950). Comments on a Mechanistic Conception of Purposefulness. Philosophy of Science. doi:10.1086/287106
3. Rosenblueth & Wiener (1950). Purposeful and Non-Purposeful Behavior. Philosophy of Science. doi:10.1086/287107
4. Taylor (1950). Purposeful and Non-Purposeful Behavior: A Rejoinder. Philosophy of Science. doi:10.1086/287108
5. Galison (1994). The Ontology of the Enemy: Norbert Wiener and the Cybernetic Vision. Critical Inquiry. doi:10.1086/448747
6. Bowker (1993). How to be Universal: Some Cybernetic Strategies, 1943-70. Social Studies of Science. doi:10.1177/030631293023001004
7. Heims (1991). The Cybernetics Group. Cambridge, MA: MIT Press.
8. Kline (2015). The Cybernetics Moment: Or Why We Call Our Age the Information Age. Baltimore: Johns Hopkins University Press.
9. Wiener (1948). Cybernetics: Or Control and Communication in the Animal and the Machine. Paris: Hermann; Cambridge, MA: Technology Press; New York: Wiley.

see also