In hedonic theories of motivation, ‘motivational affective states’ (MASs) are typically seen as adaptations which motivate certain types of behaviour, especially in situations where a flexible or learned response is more adaptive than a rigid or reflexive one. MASs can be negative (eg unpleasant feelings of hunger or pain) or positive (eg pleasant feelings associated with eating and playing). Hedonic theories often portray negative and positive MASs as opposite ends of a one-dimensional scale.

We suggest that natural selection has favoured negative and positive affect as separate processes to solve two different types of motivational problems. We propose that negative MASs (eg thirst, fear) evolved in response to ‘need situations’ where the fitness benefit of an action has increased, often because the action is needed to cope with a threat to survival or reproductive success. We propose that these negative MASs develop in response to a change in the body (eg dehydration) or the environment (eg the approach of a predator) which creates the need for action, and that negative MASs can become intense and prolonged if the threat to fitness is high and persistent. We propose that positive MASs evolved in ‘opportunity situations ‘ where an action (eg playing, exploring) has become advantageous because the fitness cost of performing it has declined. We propose that these positive MASs occur during, or as a result of, the performance of types of behaviour which are beneficial for fitness at a variety of times, not only when they are required to meet immediate needs; and that the pleasure inherent in the behaviour motivates the animal to perform it when the cost of so doing is sufficiently low. Some behaviour (eg eating) can be motivated by both positive and negative affect. Other behaviour, such as playing or fleeing from a predator, may be motivated largely by positive or negative affect alone. Our hypothesis needs to be tested, but we suggest that it corresponds well to common human experience.

The hypothesis provides a basis for predicting whether an aspect of animal management is likely to cause strong and prolonged negative affect (‘suffering’), or to prevent animals from experiencing certain types of pleasure. This distinction is important for bringing animal welfare assessment into line with ethical concerns.

It is a popular notion that, compared to vertebrates, invertebrates have a reduced capacity to experience suffering. This is usually based on arguments that invertebrates show only simple forms of learning, have little memory capacity, do not show behavioural responses to stimuli that would cause ‘higher’ vertebrates to exhibit responses indicative of pain, and have differences in their physiology that would preclude the capacity for suffering. But, how convincing is this ‘evidence’ of a reduced capacity to suffer? Suffering is a negative mental state - a private experience - and, as such, it cannot be measured directly. When assessing the capacity of an animal to experience suffering, we often compare the similarity of its responses with those of ‘higher’ animals, conceptualized in the principle of argument-by-analogy. By closely examining the responses of invertebrates, it can be seen that they often behave in a strikingly analogous manner to vertebrates. In this paper, I discuss published studies that show that invertebrates such as cockroaches, flies and slugs have short- and long-term memory; have age effects on memory; have complex spatial, associative and social learning; perform appropriately in preference tests and consumer demand studies; exhibit behavioural and physiological responses indicative of pain; and, apparently, experience learned helplessness. The similarity of these responses to those of vertebrates may indicate a level of consciousness or suffering that is not normally attributed to invertebrates. This indicates that we should either be more cautious when using argument-by-analogy, or remain open-minded to the possibility that invertebrates are capable of suffering in a similar way to vertebrates.

There are conflicting views about the humaneness of the handbow as a recreational hunting method for deer. Some claim that it is the most humane hunting method, whilst others report higher wounding rates and crippling losses than with the rifle. This commentary summarises the factors affecting the likelihood of a quick death, the types of equipment commonly used, the vital target areas, the influence of blood loss on blood pressure and brain function and the prevalence of wounding during routine bowhunting. Some requirements in Bowhunters Association Codes of Conduct are also described. It is concluded that where bowhunting is allowed, Codes of Conduct should emphasise the hunters' responsibility to track and despatch injured animals, and adherence to the Codes should be encouraged, if not enforced.

The scientific study of animal welfare has generated a welter of complex, equivocal and often contradictory results. Consequently, there is little agreement about how impairment of welfare should be measured. While some solutions to this have been suggested, these have usually relied on more sophisticated versions of, or more control over, existing measures. However, we argue that the difficulties arise because of questionable assumptions in the definition and measurement of welfare, in particular the measurement of suffering and the assumed importance of individual well-being. We contend that welfare can be interpreted only in terms of what natural selection has designed an organism to do and how circumstances impinge on its functional design. Organisms are designed for self-expenditure and the relative importance of self-preservation and survival, and the concomitant investment of time and resources in different activities, varies with life history strategy. The traditional notions of coping and stress are anthropomorphisms based on homeostatic mechanisms of self-preservation in a long-lived species. Suffering-like states are viewed as generalized subjective states that are geared to avoiding deleterious circumstances with which the organism does not have specific adaptive mechanisms to deal. Attempts to measure suffering-like states directly are likely to remain inconclusive, at least for the foreseeable future, because such states are private and subjective, may take many forms fundamentally different from our own and are likely to depend on the operation of phenotype-limited priorities and decision rules. However, measuring the impact of circumstances on functional design via the organism ‘s decision rules provides a practicable means of giving benefit of the doubt by indicating when suffering, or an analogous subjective state, is likely.

Disease is one of the most important causes of animal suffering. When diseases are treated the aim is to achieve rapid and permanent recovery and this helps to reduce the duration of suffering. It does not, however, alleviate suffering during the fulminant and recovery phases. Greater attention needs to be given to alleviating suffering and the signs of sickness during disease states. In this paper, the role of the cytokines in mediating sickness behaviour and suffering during disease is reviewed. The importance of sickness behaviour in improving the chances of recovery are considered, along with the potential use of anti-cytokine strategies in alleviating suffering in disease states.

Humans interact with fish in a number of ways and the question of whether fish have the capacity to perceive pain and to suffer has recently attracted considerable attention in both scientific and public fora. Only very recently have neuroanatomical studies revealed that teleost fish possess similar pain-processing receptors to higher vertebrates. Research has also shown that fish neurophysiology and behaviour are altered in response to noxious stimulation. In the light of this evidence, and in combination with work illustrating the cognitive capacities of fish, it seems appropriate to respond to a recently published critique (Rose 2002) in which it is argued that it is not possible for fish to experience fear or pain and that, therefore, they cannot suffer. Whilst we agree with the author that fish are unlikely to perceive pain in the same way that humans do, we believe that currently available evidence indicates that fish have the capacity for pain perception and suffering. As such, it would seem timely to reflect on the implications of fish pain and suffering, and to consider what steps can be taken to ensure the welfare of the fish that we exploit.

The culling of injured and non-viable pigs (Sus scrofa) (neonate to breeding stock) is a routine and necessary procedure on most farms. Usually, pigs are culled using one of the following methods: blunt-force trauma (manual and mechanical), captive-bolt stunners, electrical stunning and electrocution or carbon dioxide. Manual blunt-force trauma is one of the most widely used methods due to its low or absent operational and investment costs. However, as a method, it has serious limitations, which include the risk of incomplete concussion, pain, and distress. Manual blunt-force trauma is also aesthetically unpleasant to operators and wider society. To address these issues there has been significant recent research into the development of alternatives to manual blunt-force trauma, these include: captive-bolt stunners, on-farm, gas-based controlled atmosphere systems, low atmospheric pressure systems and electrical stunning. Some of these are currently in commercial use while others are still in the developmental phase. This review brings together the relevant research in this field, evaluating the methods in terms of mechanism of action (mechanical and physiological), effectiveness and animal welfare.

Contributing to modern theology's attention to diverse embodiments and particular histories, this paper brings the poetry of the book of Job into dialogue with new voices: modern poets of disability, especially women. Traditional theological reflections on suffering and disability often turn to Job, although Job's words and the text itself resist easy conclusions. Modern poets of disability reveal surprising similarities with Job, as both seek to reject the meaning others ascribe to their bodies. Comparing the poets of disability to Job reveals how disabling change to the body is experienced as exile and as a new experience requiring new language. The unchanged, able-bodied audience rejects the new insights of the poet, exposing the conflicts between the interpretations that communities privilege and those they exclude. Elements of a constructive theology of disability are found in the way poets of disability creatively reconfigure the changing relationships among body, words, community, and God.

This article adds to our understanding of late medieval women's religious writing by examining the role of the Virgin Mary in Mechthild of Magdeburg's thirteenth-century mystical text The Flowing Light of the Godhead (Das fließende Licht der Gottheit). The Virgin Mary was ubiquitous in late medieval religious writing, but she played different roles and modeled different ways of life, reflecting the particular aims of individual authors. In Mechthild's text, Mary is depicted as a spiritual teacher who actively draws the narrator into higher forms of the mystical life. Mechthild also portrays the Virgin in several traditional roles, adapting each of these roles to support her particular vision of the mystical life. Mary thus functions as a model for religious experience in The Flowing Light, while also authorizing and sanctioning Mechthild's contemplative ideals.

Kant’s theory of friendship is crucial in defending his ethics against the longstanding charge of emotional detachment. But his theory of friendship is vulnerable to this charge too: the Kantian sage can appear to reject sympathetic suffering when she cannot help a suffering friend. I argue that Kant is committed to the view that both sages and ordinary people must suffer in sympathy with friends even when they cannot help, because sympathy is necessary to fulfill the imperfect duty to adopt others’ merely permissible ends (MPEs), and we ought to take friends’ MPEs as our own. MPEs are individuated in terms of concepts which include marks of the first person, and no marks of law other than permissibility. To adopt ends of others individuated in terms of such concepts rather than merely promote them as means to different ends, those concepts must engage with one’s feelings in a way that requires sympathy.

The Book of Job treats of the Problem of Evil. It is divided into two documents: (1) the framework story, that is, the Prologue and the Epilogue (Job 1:1–2:13; 42:7–17); and (2) the speeches by Job, his friends, and God. In the framework story, Job is presented as a just man who serves God in good times and bad (Job 1:21; 2:10). In the speeches, God is accused by Job of ‘destroying the hope of man’ (Job 14:19). God replies with an ad hominem argument: ‘Where were you when I laid the foundation of the earth?’ (Job 38:4). If God argues that it is unfair for humans to judge God, Job argues that it is unfair for God to judge humans.