Confuses rules of conduct with rules of behaviour
We can't formulate a complete set of rules of conduct for human performance, but human behaviour is still governed by natural laws that can in principle be given a mechanical description—and hence it's possible to build a machine to fit this descript
Rules of Conduct: "Precepts, such as 'Stop if you see red lights,' on which one can act, and of which one can be conscious."
Laws of Behaviour: "Laws of nature as applied to man's body, such as 'If you pinch him, he will squeak'."
Alan Turing 1950, (both quotes from p.452)