The discourse surrounding sustainable consumption and production has evolved to encompass sufficiency strategies in addition to efficiency and effectiveness. Product-service systems (PSSs) can promote sufficiency by replacing traditional product-intensive systems with dematerialized services and changes in ownership structures. Sufficiency-oriented PSS may, however, generate rebound effects which offset potential sufficiency benefits or even result in backfire. This paper examines the connection between sufficiency-oriented PSS and rebound reviewing 12 empirical studies addressing rebound.

The concept of voluntariness permeates the ethics and politics of migration and is commonly used to distinguish refugees from migrants. Yet, neither the precise nature and conditions of voluntariness nor its ethical significance for migrant rights and state obligations has received enough attention. The articles in this collection move the debate forward by demonstrating the complex ethical judgments involved in delineating voluntary from forced migration and in drawing out its political and institutional implications. In addition to highlighting the interplay between the voluntary and nonvoluntary elements of migration over time and across different sites of the migration journey, they provide a nuanced account of the various conditions of voluntariness and they challenge common ideas about its normative political consequences.

A key question in the theory of migration and in public debates on immigration policies is when migration can be said to be voluntary and when, conversely, it should be seen as nonvoluntary. In a previous article, we tried to answer this crucial question by providing a list of conditions we view as sufficient for migration to be considered nonvoluntary. According to our account, one condition that makes migration nonvoluntary is when people migrate because they lack acceptable alternatives to doing so. In this article, we take the opportunity to further explore and clarify this crucial condition. More specifically, we focus on two main sets of questions. First, we ask whether migration is always voluntary when it serves goals that are voluntarily chosen, and whether those who decide to migrate voluntarily but only have the option of choosing among a limited set of dangerous, harmful, or illegal means for doing so, can be said to be forced to choose those means. Second, we ask whether what counts as “nonacceptable” alternatives should also include cases in which people could have their needs and fundamental rights met, but at the cost of betraying their moral principles or conceptions of the good.

In this article I argue that the non-reciprocity problem does not apply to intergenerational justice. Future generations impact, here and now, on the well-being of people now living. I firstly illustrate the economic-synchronic model of direct intergenerational reciprocity (DIR): future generations allow people now living to maintain the economic system future-oriented and capital-preserving. The rational choice for people now living is to guarantee transgenerational sufficiency to future generations. I then analyse the axiological-synchronic model of DIR: future generations give meaning and value to many of the activities that people now living carry out, and this is a compelling reason for the latter to worry about the former. I argue that only the economic-synchronic model of DIR can consistently explain why we need future generations. I conclude by discussing the limits of indirect intergenerational reciprocity.

Exponential random graph models, or ERGMs, are a flexible and general class of models for modeling dependent data. While the early literature has shown them to be powerful in capturing many network features of interest, recent work highlights difficulties related to the models’ ill behavior, such as most of the probability mass being concentrated on a very small subset of the parameter space. This behavior limits both the applicability of an ERGM as a model for real data and inference and parameter estimation via the usual Markov chain Monte Carlo algorithms. To address this problem, we propose a new exponential family of models for random graphs that build on the standard ERGM framework. Specifically, we solve the problem of computational intractability and “degenerate” model behavior by an interpretable support restriction. We introduce a new parameter based on the graph-theoretic notion of degeneracy, a measure of sparsity whose value is commonly low in real-world networks. The new model family is supported on the sample space of graphs with bounded degeneracy and is called degeneracy-restricted ERGMs, or DERGMs for short. Since DERGMs generalize ERGMs—the latter is obtained from the former by setting the degeneracy parameter to be maximal—they inherit good theoretical properties, while at the same time place their mass more uniformly over realistic graphs. The support restriction allows the use of new (and fast) Monte Carlo methods for inference, thus making the models scalable and computationally tractable. We study various theoretical properties of DERGMs and illustrate how the support restriction improves the model behavior. We also present a fast Monte Carlo algorithm for parameter estimation that avoids many issues faced by Markov Chain Monte Carlo algorithms used for inference in ERGMs.

More nation states are now committing to zero net carbon by 2050 at the latest, which is encouraging, but none have faced up to the transformation of economies, societies and lives that this will entail. This article considers two scenarios for a fair transition to net zero, concentrating only on climate change, and discusses the implications for contemporary ‘welfare states’. The first is the Green New Deal framework coupled with a ‘social guarantee’. I argue that expanded public provision of essential goods and services would be a necessary component of this strategy. The second scenario goes further to counteract runaway private consumption by building a sufficiency economy with ceilings to income, wealth and consumption. This would require a further extension of state capacities and welfare state interventions. The article provides a framework for comparing and developing these two very different approaches.

The idea of pooling resources and sharing risks to provide universal services according to need not ability to pay was at the heart of the post-war settlement. However, decades of market ideology and deep spending cuts have left most services starved of power and resources. Universal Basic Services (UBS) offers a principled framework for policy and practice that aims to ensure everyone has access to life’s essentials. Based on need theory it combines universality with sufficiency to provide a secure social foundation for all within planetary boundaries. Needs are met in different ways, combining collective and individual measures, as illustrated by examples of childcare, housing and food. UBS can be combined with an income guarantee to ensure no-one’s income falls below an agreed level of sufficiency. Cash and services, which represent a ‘social wage’, are best understood as two sides of the same coin, supporting rather than competing with one another.

The goal of this article is to diagnose a verbal construction which has made it to common use in Austrian German and is typically unknown to many speakers of Federal German who have not been exposed to Austrian German. This construction is based on the verb gehen (‘go’) conjoined by a particle and the reflexive. An argument for its analysis as a degree-based sufficiency construction is developed, which is constructed by extending existing approaches in the literature on enough constructions and suggesting a meaning of the construction at hand, which is presuppositional in multiple respects. The results of diachronic corpus searches as well as the significance of the results of this work for the space of possibilities of the semantic change of motion verbs are discussed.

The standard version of sufficientarianism maintains that providing people with enough, or as close to enough as is possible, is lexically prior to other distributive goals. This article argues that this is excessive – more than distributive justice allows – in four distinct ways. These concern the magnitude of advantage, the number of beneficiaries, responsibility and desert, and above-threshold distribution. Sufficientarians can respond by accepting that providing enough unconditionally is more than distributive justice allows, instead balancing sufficiency against other considerations.

Samuel Moyn argues that the human rights movement, which thrived in the 1970s and peaked after the Cold War, became dominated by a misplaced focus on sufficiency rather than equality, ultimately abetting neoliberalism. He deplores the rise and fall of an egalitarian and redistributive worldview, from the Jacobin era to the slow decline of socialism in the twentieth century, culminating in ineffectual and unambitious human rights endeavors. Here Moyn cavalierly dismisses the enormous achievements of the human rights movement in many countries, overlooking the contributions of unsung heroes who fought for human rights at the peril of their lives. Even readers who share Moyn's political perspective will find little solace, either in the form of lessons learned or in forward-looking strategies for addressing socioeconomic inequity and other human rights violations of our time.

The intensity of a stationary process of k-dimensional affine subspaces (k-flats) of ℝd with directional distribution from a given family R is estimated by observing the process in a compact window. To this end we introduce a type of unbiased estimator (the R-estimator) using the available information about the directional distribution.

Special cases are estimators for the intensity of stationary k-flat processes (1) with known directional distribution, (2) with directional distribution invariant with respect to a subgroup of the group of rotations in ℝd and (3) with unknown directional distribution.

We give sufficient conditions for the R-estimator to be the uniformly best unbiased estimator for the intensity of stationary Poisson k-flat processes with directional distribution in R. Equivalent statements for certain types of stationary Cox flat processes can be deduced directly from the results in the Poisson case.

Moreover, we consider stationary ergodic flat processes with directional distribution in R and general stationary flat processes with unknown directional distribution, all with a non-degeneracy property. In both cases our estimator turns out to be the uniformly best unbiased estimator from a restricted set of estimators. The result for general stationary flat processes is proved with the help of a factorization result for the second factorial moment measure.