An Evolutionary Perspective

Intentionally created and evolutionary perspectives

Economists have developed two perspectives on institutional change: the intentionally created perspective and the evolutionary perspective/¹ The intentionally created perspective holds that forward-looking individuals deliberately create institutions, in order to serve various functions, and it deals with the responses to these functions.

It appears, however, that within contemporary social evolutionary theory the intentionally created perspective is integrated. Richerson and Boyd observe:

Darwinian tools help us build linkages between phenomena at different levels as given problems require. Individuals seem to be hapless prisoners of their institutions because, in the short run, individual decisions don’t have much effect on institutions. But, in the long run, accumulated over many decisions, individual decisions have a profound effect on institutions. Evolutionary theory gets right the basis structure of the relationship between individuals and the collective properties of their societies/⁶

The same perspective is chosen in this book for legal history. No one has constructed the formulary procedure or drafted the praetor’s edict from scratch: they are the result of long-term incremental evolutionary processes. As Schulz observed in respect of the formulae for the bonei fidei iudicia: ‘these formulae were gradually developed and were not framed by one man accord­ing to a comprehensive plan/⁷ Nevertheless, generations of Roman jurists have shaped legal evolution by consciously assimilating contractual innovations into the existing legal framework and incrementally building up a complex body of legal rules.

The origin and content of the actio Serviana may have been closely connected to the interdictum Salvianum and, in any case, will have built upon existing transactional practices (e.g., Cato's pledge templates).^[88] Moreover, even a great mind like Servius could not have planned the evolutionary path the actio Serviana would take in the three centuries following its creation, enfor­cing multiple pledges, pledges of claims, and even ‘floating' charges over all the debtor's assets. The Roman law of pledge is ‘far too complex for even the most gifted innovator to create from scratch’.^{[89] [90] [91] [92] [93] A good evolutionary theory of legal change can provide a balanced account of legal evolution as a combination of unplanned and incremental processes and the intentional acts of individuals.}

Evolution of law

The available sources for legal history have, according to Luhmann, not been sufficiently evaluated from a theoretical perspective/¹ This can only be achieved through concepts of evolutionary theory/² The evolutionary ana­lysis of law is an integral part of Luhmann's social systems theory in order to describe how legal systems adjust to changing conditions/³ Thus, building upon Luhmann, Deakin formulates an evolutionary theory of legal change which is based on three related propositions.

The first is that legal evolution is cumulative: incremental mutations in legal forms, when coupled with the selective effect of environmental pressures, can give rise to complex, multifunctional legal institutions. Secondly, legal forms are adaptive without being optimal.

The fundamental thesis of evolutionary social scientists (including lawyers and economists) is that not only living organisms are subject to Darwin's ‘descent with modification' but also social, economic, and cultural phenomena such as languages, scientific theories, organizations, and legal institutions.^{[94] [95] [96] [97] [98] [99] [100] [101]} This generalized Darwinism is not all about biological metaphors and analogies.8⁶ Socio-cultural evolutionary scholars have identified specific evo­lutionary processes in the social and cultural world, in which human inten­tionality does plays an important role/⁷ One of the evolutionary processes which is different in socio-cultural evolution is biased transmission: based on their content, people adopt some cultural variants rather than others accord­ing to their own cultural and cognitive biasesTh Like natural selection, biased transmission is a culling process (‘a process of selective retention')/⁹ but it is not identical to it. Biased transmission is dependent on human preferences, choices, and desires, whereas in most forms of natural selection the fitness of genes depends on their effect of reproduction independent of human intentionality/⁰ Very different from its biological counterpart and crucial for social and legal evolution is guided variation: the changes that are transmitted are not random but the result of adaptive modifications which are deliberately made by humans/¹ Biased transmission and guided variation together are ‘decision-making forces', which are based on learning rules and are likely to be subject to many of the same psychological mechanisms.

What exactly is the nature of the information which is the object of pro­cesses of legal evolution? Dawkins has coined the term ‘replicators' in order to designate the packages of information that are changed and transmitted in evolutionary processes.^[102] These replicators are often regarded as ‘miniscule, genelike particles that are faithfully replicated during cultural transmission' (e.g., memes).9^[103] Richerson and Boyd observe, however, that what they call cultural variants sometimes are ‘somewhat genelike, while at other times they decidedly are not'. They must be gene-like to the extent that they carry cul­tural information, but ‘this can be accomplished in most un-genelike ways?^[104] Darwin himself had a very un-gene-like picture of inheritance but this did not matter because evolutionary processes ‘are tolerant of how heritable vari­ation is maintained?^[105] Nevertheless, in law we do have replicators that would even satisfy the strict demands of ‘universal Darwinists' such as Hodgson and Knudsen. In order to define replicators they refer to biologist Ernst Mayr, who characterizes replicators as programmes?^{[106] [107] The programme-like charac­ter of legal rules appears to make them suitable candidates for being legal replicators. In late republican and classical Roman law legal evolution takes place by the creation or modification of conditional programmes encapsu­lated in forms of action (formulae).9* A legal institution can be regarded as the aggregate of the legal rules which determine the development of legal relationships of a certain type (e.g., sale, partnership, pignus, hypotheca, and fiducia). Evolutionary sequences of variation, selection, and replication may change conditional programmes contained in legal rules, so that the legal institutions to which they apply acquire different traits: this is evolution of law.}

A proper theory of legal evolution

The right method for building a theory of legal evolution is, at this stage, neither deductive nor aimed at logical correctness in the use of Darwinian evolutionary concepts.99 We first have to find out exactly how processes of variation, selection, and inheritance operate within legal systems. After microevolutionary processes operative in law have been identified and analysed, it could then be tested whether they can be generalized and are logically compatible with the Darwinism elaborated by evolutionary social scientists.¹⁰⁰ This is not a task I have set for myself in this book. My evolutionary approach boils down to historical narratives of how legal evolution consists of long-term cumulative and adaptive processes, involving mechanisms which can be labelled as ‘variation', ‘selection, and ‘inheritance'. For the purpose of this book I use the following working definitions of these mechanisms. A legal variation (or variant) is a modified (including differently interpreted) copy of an existing legal rule, form of action (formula), or legal institution (e.g., new variant of pledge).¹⁰¹ There is selection if a judicial (praetor, iudex, emperor), legislative, or other legally recognized authority (e.g., jurist with ius respondendi) recognizes the variation as positive law,™² either incidentally (e.g., actio in factum) or structurally. In the latter case there is stabilization (‘inheritance': replication, retention, transmission): a legal variant remains part of positive law and will thus continue to determine the legal consequences of future legal relationships. Although certainly in Rome ‘doctrinal structures' did have a stabilization function,™³ there were also other important stabilization mechanisms, such as the praetor's edict, legislation, and a doctrine of prece­dent in imperial constitutions.™⁴

From systems theory I accept that although legal evolution may be trig­gered by the economic environment, the legal system itself determines whether this takes place and in what form. The operative closure of the legal system therefore limits its capacity for legal change, while at the same time it contributes to its stability.10⁵ The functional differentiation of society into autopoietic subsystems entails that within an evolving society an independent evolution of law is possible. From the perspective of the legal system this means that the economy may produce ‘irritations', which are processed by evolutionary mechanisms operating within the legal system.¹"⁶ From the per­spective of the economic system, this co-evolution entails that legal changes (e.g., legislation enacted to regulate prices) can have economic effects, but these effects are determined by economic ‘laws' rather than by the legal sys­tem. The evolution of law cannot, therefore, be treated as simply mirroring the evolution of certain other parts of society (e.g., politics, economy,

i"i Luhmann 2004: 247-8: ‘Variation attended to the mutation of law (which is largely unsuccessful but occasionally can be confirmed). Without it, no evolutionary changes would be possible.'

i"2 Luhmann 2004: 248: ‘Selection attends to the task of defining which opinion is in accordance with the legal system.'

I"³ Teubner 1988: 228; Luhmann 2004: 340.

i"4 For variation, selection and stabilization mechanisms in Roman law, see in particular chapter 2.

I"⁵ Teubner 1988: 231.

I"⁶ Deakin 2011: 675; Teubner 1988: 228; Vesting 2018a: 152.

religion).^{[108] [109] [110] [111] [112] [113] [114] This also has the consequence that system-specific time frames develop. The legal system may be ‘out of synch' with the economy and only give in to economic selection pressures after a long time (e.g., multiple pledge).io8}

Evolutionary functionalism: evolutionism

A formidable critique on evolutionary, systems, and economic perspectives on legal history comes from Gordon. In his Critical Legal Histories (1984), Gordon's purpose was to ‘describe and critique a grand theory', which he calls ‘evolutionary functionalism'.¹¹¹⁹ In Gordon's perception this theory has two components. The first—‘evolutionary'—part is ‘that there is a process of social development common to most “advanced” or “dynamic” societies, culminat­ing in modernity'.iio What Gordon calls ‘evolutionary' is called ‘evolutionist' by socio-cultural evolutionary scholars and is firmly rejected in modern evo­lutionary analyses of social and legal changed“ There is neither a universal sequence of stages of legal change nor is there a ‘predestined convergence on a single, uniquely efficient form or “evolutionary peak” '.“² In an important con­tribution on law, economics, and evolutionary theory, Roe observes: ‘eco­nomic evolution selects out for extinction very inefficient results, and efficient results tend to survive'.“³ This evolution-to-efficiency paradigm must be used with care (as Roe readily admits).“⁴ As a conjecture one can maintain that it is plausible that grossly inefficient legal institutions are unlikely to survive. At the same time one must realize that legal evolution is conditioned by the operative closure of the legal system and heavily dependent upon historical contingencies and other factors (e.g., governmental policies, religion, culture), which may prevent the most efficient outcome being reached.“⁵ It therefore will not do, for instance, to simply say that because fiducia lost the struggle for existence against pignus and hypotheca it must have been less efficient. This may ultimately very well have been the reason, but this does not discharge the researcher from the obligation to search for specific historical factors which may have contributed to the demise offiducia.¹¹⁶ One cannot assume that within a legal system there is an intrinsic trend toward efficiency (or complexity). This is something that detailed legal-historical research has to prove or falsify for each legal institution and each legal system.

Legal evolution is a historical process, which for each legal system is a unique one. The evolutionary process is, also in autonomous (autopoietic) legal systems, to a large extent one of intermittent adaptation triggered by the law's environment. If environments differ (as they always do), legal evolution will be different as well.“⁷ But all this is not to say that no regularities— evolutionary trends—can be discerned.“⁸ A basic fact of comparative law is that in societies with similar socio-economic structures similar legal institu­tions emerge.“⁹ Thus, legal systems operating in modern free market econ­omies all have individual ownership rights, freedom of contract, limited liability companies, and real security rights, irrespective of whether they belong to the common law or the civil law tradition?²⁰ The many exceptions to this statistical law demonstrate, however, that evolving legal systems must have a ‘higher potential of autonomy' than purely economic theories of legal evolution predict.121 With economic historian Joel Mokyr, I believe that an evolutionary approach ‘places the analysis between the extremes of a materi­alist analysis that regards historical outcomes as inexorable and foreordained and a nihilist approach that sees nothing but randomness everywhere'.122

Evolutionary functionalism: functionalism

The second—‘functionalist'—part of evolutionary functionalism identified by Gordon is that legal systems can be viewed as providing ‘adaptive responses'

i¹⁶ Section 4.6.

i*7 On the generality of evolutionary analysis and the specificity of historical analysis see Richerson and Boyd 2005: 245-8; Morris 2015: 11-3; Lewens 2015: 160-1, 183; Mokyr 2017: 9, 22-33. See also Popper 1973: 270.

118 See Richerson and Boyd 2005: 60, 96; Jablonka and Lamb 2014: 223; Sanderson 2007: 276.

119 Zweigert and Kotz 1998: 40.

120 Some of these legal institutions are legal transplants (e.g., the Dutch United East India Company (VOC) served as a model for English companies). The laws of real security of common law and civil law jurisdictions seem to have evolved independently, but still share many features. See Verhagen 2013b.

121 Teubner 1988, 229. For a selection of articles on the ‘efficient evolution' of Anglo-American common law, see Rubin 2007.

122 Mokyr 2017: 32. See also Richerson and Boyd 2005: 246-8; Bresson 2016: 22. to social needs; law as a ‘dependent variable’.^{[115] [116] [117]} It is, however, according to him inherently impossible to establish strong causal links between economic needs and legal responses to these needs. Gordon observes that:

saying things like ‘the negligence principle’ or ‘property rights in land’ were preconditions to, or even just very favorable legal environments for, eco­nomic growth, ignored the basic insight of Legal Realism—the myriad ways in which legal doctrines can be interpreted and differentially applied or ignored or worked around on the way to enforcement.^⁴

Gordon’s criticism in statements like this is to a large extent certainly justified. In particular, economic analyses on the contribution of ‘property rights’ to economic growth in past societies sometimes suffer from generalizations which are either too general to be meaningful or not supported by historical evidence.12⁵ The autonomous nature of the legal system entails that a purely adaptionist approach, in which the law always and immediately responds by adopting rules that serve economic needs, is inappropriate?²⁶ Moreover, cer­tainly in relation to ancient societies, it is often already very difficult or impos­sible to establish correlations, let alone to prove that correlation and causation coincide. Compared with the sources that are available for contemporary laws, and even compared with those concerning medieval and early modern laws, data allowing us to do so are scarceTh⁷ Where correlations between eco­nomic change and legal evolution do appear to exist, causal links can often only be made plausible.

What can be proven, however, is that in many instances legal evolution is triggered by transactional practices. Certainly if realistic assumptions can be made in respect of the economic rationality of the transacting parties (or their legal counsel),i2⁸ the identification of transactional practices will allow us to make plausible inferences about the law responding to economic needs. The findings of detailed empirical economic analyses of contemporary collateral laws can then be applied to Roman law in order to examine whether the accommodation of transactional practices into the existing legal framework did create a favourable legal environment for economic growth. Above all, ‘crude functionalist accounts’ of the origin and evolution of legal institutions can be avoided by ‘studying the dynamics of how the institution was created over time’.^[118] This is precisely the purpose of the detailed historical accounts on the origin and evolution of the variants of pledge in this book.

Evaluation

Even at this stage, where no unified evolutionary synthesis of social and legal evolution exists, it may still be useful to employ the ‘evolutionary algorithm’¹·¹" of variation, selection, and inheritance (stabilization) to organize one’s thoughts about the co-evolution of law, economy, and other subsystems of society.i³i Although I do not assume (however plausible this may be) that these evolutionary processes are truly Darwinian, this will not prevent me from tapping into the ‘collective wisdom’ of evolutionary social scientists whenever I think this is possible and useful.^ There is much to learn from evolutionary approaches developed for other areas of the socio-cultural domain.1³³ In one of their joint contributions on evolutionary theory and his­tory, historian Joseph Fracchia and evolutionary biologist Richard Lewontin ask sceptically: ‘What constitutes an evolutionary process as opposed to a “merely” historical one? What explanatory work is done by claiming that cul­ture has evolved?’^⁴ The answer is that legal evolution is something other than merely legal change: it is—in the words of Frier—‘adaptation in response to external stimuli’?³⁵ Although I accept that to a certain extent my evolution­ary approach consists of a borrowed set of metaphors and analogies, it is more than that.i3⁶ Triggered by their economic, political, or religious environment, legal institutions originate or change: they become more (or less) complex, display enhanced (or decreased) adaptedness, or disappear.^⁷ These are real evolutionary processes operating within legal systems.^⁸ Most legal institu­tions ‘did not emerge in one single step, but are the result of cumulative his­torical processes’^ Legal evolution is (like cultural evolution) ‘an instance of general evolution, in the full, nontrivial sense of cumulative, adaptive, open- ended change’.¹⁴⁰ Legal evolution is an evolutionary process in its own right.

1.4