Ayer, A. J., (1956)
"What is a Law of Nature" (Argues against the simple regularity
theory of laws of nature. Suggests a theory of the form: law of nature
= universal truth + X, where X is a set of epistemic factors.)
[R]
Popper, Karl (1967), "A Revised Definition of Natural Necessity," British
Journal for the Philosophy of Science, 18, 316-321. [Proposes an
account of the form: law of nature = universal truth + X], where
X is a matter of satisfying a non-deducibility requirement.]
Michael Tooley
(1977) “The Nature of Laws” (Criticizes a number of theories
of natural laws. Proposes a theory on which causal relations are contingent
relations among universals.) [R]
Skyrms, Brian (1977)
"Resiliency, Propensities, and Causal Necessity." (Proposes
a theory of laws of the form: law of nature = universal law + X,
where X concerns the kind of evidence available.)
Armstrong, David
(1983) What is a Law of Nature? (Contains an excellent critical
discussion of regularity theories of natural law. Proposes a theory
on which causal relations are contingent relations among universals.)
Tooley, Michael
(1987) Causation, Oxford University Press, Parts I-II, pp. 1-169.
(Contains an excellent critical discussion of the regularity theories
of natural law and their variants. Proposes a theory on which causal
relations are contingent relations among universals. Argues for differences
between his own account and that of Armstrong (1983).)
Tooley, Michael
(1990), "Causation: Reductionism versus Realism," sections
1-2. (The first two sections of the paper contain a summary of some
of the leading objections to regularity theories of natural law and
their variants.) [R]