(Ashgate, 2004). However, if one doubts that the relationship between the rule of recognition
and rules of legal inference might resemble the relationship between logical terminology and
logical rules of inference that is posited by the conventionalist tradition, it is not clear what
other resources the Hartian has to draw upon to account for the content of the rules of legal
inference, and their validation. Rather, the alternative seems to be to adopt the ‘thin’ picture.
The Centrality and Diversity of the Invisible Constitution
159
This conclusion may seem commonplace or even trivial, because already
well-established by scholarship on comparative law and legal cultures. It may
nevertheless be of interest to see how a relatively mainstream analytic juris-
prudential approach to the study of constitutional orders leads to the same
conclusion.
5.4. ‘Thin’ Validation and Invisibility
The ‘thick’ picture of validation discussed in the previous section is distin-
guished by the claim that even unexpressed laws – that is to say, laws not
expressly or self-evidently stated by an authoritative source – must be validated
by the rule of recognition. The ‘thin’ picture, by contrast, extends the demand
for validation only to the authoritative sources themselves. When it comes to
working out the laws that are stated by or follow from these sources, on the
other hand,
such argumentation does not itself require a rule of recognition to operate
recursively upon its results. All it requires is a way of identifying the texts
around which casuistry and interpretive argumentation will revolve.
33
On the ‘thin’ picture, identifying the content of the law – including the con-
tent of the constitution and the other legal content that follows from it – will
depend upon particularities of acceptable method. We can therefore expect
that different legal cultures, with differing methodologies for deriving the law
from texts, will be apt to draw very different conclusions about the law even
if confronted with identical texts. For instance, in some legal cultures it may
be considered permissible to reason back from the rules stated in a legal text
33
Waldron, ‘Who Needs Rules of Recognition’ in Matthew Adler and Kenneth Einar Himma
(eds.),
The Rule of Recognition and the U.S. Constitution (Oxford: Oxford University Press,
2009), 349. Although in this essay Waldron does not use the terminology of ‘thick’ and ‘thin’,
he clearly draws the distinction, and also expresses a preference for the ‘thin’ picture, when
he asks (336) ‘why did Hart think it plausible to talk about a fundamental rule for recognizing
rules of law, as opposed to a rule for recognizing
sources of (rules of) law? I know of no good
answer’. Waldron also argues (332, 339–45, 348–9) that, once the focus is on sources, then
rather than a rule of recognition our principle concern should be with the rule of change (i.e.,
the rule that governs the introduction of new authoritative sources into the system, and the
cancellation of existing sources), which in a typical constitutional order will be the rule that
governs the enactment of legislation and (at least in common law systems) the production
of authoritative reports of decided cases. I think that this argument is a strong one (though
Gardner disagrees: ‘Can There Be a Written Constitution’, Supra note 11, 176–8), but in this
chapter I only note it.