Experimental longtermist jurisprudence


This is a summary of the paper “Experimental longtermist jurisprudence” by Eric Martínez and Christoph Winter.

Climate change, pandemics, nuclear war, and artificial intelligence pose a grave threat to the future of humanity, yet future generations are largely ignored in legal systems. Legal institutions focus on contemporary issues and processes for the current generation, while those in the future lack democratic representation in the legislature, standing to bring forth a lawsuit in the judiciary, and serious consideration in cost-benefit analyses in the executive.

Experimental longtermist jurisprudence seeks to answer the question: What is the source of this disconnect, is it justified, and what should be done about it?

This book chapter describes experimental longtermist jurisprudence (XLJ), a new research field within experimental jurisprudence that seeks to both understand beliefs about legal longtermism and reason about how the law can and should protect future generations.

“Like other forms of experimental jurisprudence, XLJ employs methods traditionally associated with the field of experimental psychology to explore substantive questions traditionally associated with the field of jurisprudence.”

XLJ has three main foundations:

  1. Longtermism: the view that one should be particularly concerned with ensuring that the long-run future goes well
  2. Legal longtermism: the view that said concern ought to extend to the legal system
  3. Experimental legal longtermism: the practice of using experimental methods, such as surveys and controlled experiments, as a means of evaluating the validity and implications of legal longtermism

Aims of XLJ

These experimental methods are used to understand cognition and behavior relevant to legal longtermism, for example by investigating the nature of people’s beliefs regarding legal longtermism and relevant concepts, how the theory of longtermism coheres with people’s ordinary concept of rights and duties, and what contributes to those beliefs (descriptive aims: what is).

A researcher then takes on the role of a philosopher, legal theorist, lawyer, and policymaker, reasoning about the normative implications of the experimental findings (normative aims: what should be).

Levels of abstraction

Study design and reasoning may take place at three levels of abstraction. These levels have some overlap and can be undertaken independently or in tandem with each other.

Philosophical level

The philosophical level examines the nature of law, legal longtermism, and protection of future generations in an ideal legal system. The core questions at this level are:

  • Descriptive: What are people’s general beliefs about the concept of legal longtermism, and why do people hold those beliefs?
  • Normative: In an ideal legal system, how and to what extent should future generations be provided legal protection?

At this level, beliefs held by laypeople and certain experts provide the basis for normative inference using several possible approaches. For example, debunking approaches argue against assigning normative weights to judgments that are unreliable, or morally irrelevant, for example, due to cognitive bias. A pluralism approach assigns different normative weights to different groupings of participants.

Doctrinal level

The doctrinal level concerns existing legal doctrine and legal interpretation broadly, such as concepts of standing and personhood. The core questions at this level are:

  • Descriptive: To what extent does longtermism map onto people’s understanding of law, the legal system, and legally relevant concepts?
  • Normative: Under existing legal doctrine, how and to what extent can and should future generations be provided legal protection?

At this level, XLJ could be used to understand and advance legal arguments regarding the extent to which future generations can and ought to be provided legal protection according to the doctrines of current legal systems. For example, one might survey lawyers on the applicability of legal protections to future generations. Or one could seek to discover how laypeople and lawyers or other experts understand and interpret longtermism-relevant words and concepts; then, if a significant difference exists, one could argue against ordinary meaning analysis and in favor of interpretation as a word of art that has a technical meaning.

Applied (policy) level

The applied level (or policy level) concerns specific areas of law and concrete legal mechanisms and instruments—such as constitutional provisions, legislation, and regulation—and how they can and should be implemented to provide the appropriate level of legal protection to future generations. This might be through broad provisions or policy decisions designed to address specific long-term challenges such as existential risks posed by artificial intelligence, extreme climate change, and synthetic biology. The core questions at this level are:

  • Descriptive: What are people’s intuitions about how more specific areas of law and concrete legal mechanisms could address more concrete long-term challenges?
  • Normative: Which legal mechanisms and instruments can and should be implemented to provide the appropriate level of legal protection to future generations?

At the applied level, one might evaluate longtermist policies and legal instruments, for example, to identify which would most effectively protect the interests of future generations or could be most readily implemented in a given jurisdiction. One could study specific language and instruments, suitability in a particular scenario, or attempt to draw broader conclusions regarding the relative feasibility and desirability of (a) broad versus narrow provisions; (b) constitutions versus statutes, regulations, and other legal instruments; and (c) rights versus privileges, duties, and other legal concepts within longtermism-relevant legal instruments.

Much of the early work in XLJ, though promising, has only scratched the surface of the descriptive and normative questions presented here. Further research in this burgeoning field could make a great deal of progress and inform philosophical, legal, and political debates related to the long-term future.


Cite as: Van Arsdale, S. (2021, September 8). Summary – Experimental longtermist jurisprudence, by Eric Martínez and Christoph Winter, Legal Priorities Blog. www.legalpriorities.org/blog/2021/summary-experimental-longtermist-jurisprudence/.

Suzanne Van Arsdale is Research Development Specialist at the Legal Priorities Project. She holds a JD from Harvard Law School, where she was Editor-in-Chief of both the Journal of Law and Technology and the Negotiation Law Review, and graduated with three BS degrees in Biology, Biomolecular Science, and Psychology from Clarkson University.

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