Animal welfare is a concept that plays a role within both our moral deliberations and the relevant areas of science. The study of animal welfare has impacts on decisions made by legislators, producers and consumers with regards to housing and treatment of animals. Our ethical deliberations in these domains need to consider our impact on animals, and the study of animal welfare provides the information that allows us to make informed decisions. This thesis focusses on taking a philosophical perspective to (...) answer the question of how we can measure the welfare of animals. Animal welfare science is an applied area of biology, aimed at measuring animal welfare. Although philosophy of animal ethics is common, philosophy focussing on animal welfare science is rare. Despite this lack, there are definitely many ways in which philosophical methods can be used to analyse the methodologies and concepts used in this science. One of the aims of the work in this thesis is to remedy this lack of attention in animal welfare. Animal welfare science is a strong emerging discipline, but there is the need for conceptual and methodological clarity and sophistication in this science if it is to play the relevant informative role for our practical and ethical decision-making. There is thus is a strong role here for philosophical analysis for this purpose. The central aim of this thesis is to provide an account of how we can measure subjective animal welfare, addressing some of the potential problems that may arise in this particular scientific endeavour. The two questions I will be answering are: what is animal welfare, and how do we measure it? Part One of the thesis looks at the subjective concept of animal welfare and its applications. In it, I argue for a subjective welfare view - that animal welfare should be understood as the subjective experience of individuals over their lifetimes - and look at how the subjective welfare concept informs our ethical decision-making in two different cases in applied animal ethics. Part Two of the thesis looks more closely at the scientific role of welfare. Understanding welfare subjectively creates unique measurement problems, due to the necessarily private nature of mental states and here I address a few of these problems, including whether subjective experience is measurable, how we might validate indicators of hidden target variables such as welfare, how we can make welfare comparisons between individual animals and how we might compare or integrate the different types of experience that make up welfare. I end with a discussion of the implications of all these problems and solutions for the practice of welfare science, and indicate useful future directions for research. (shrink)

This paper introduces and defends an account of model-based science that I dub model pluralism. I argue that despite a growing awareness in the philosophy of science literature of the multiplicity, diversity, and richness of models and modeling practices, more radical conclusions follow from this recognition than have previously been inferred. Going against the tendency within the literature to generalize from single models, I explicate and defend the following two core theses: any successful analysis of models must target sets of (...) models, their multiplicity of functions within science, and their scientific context and history and for almost any aspect x of phenomenon y, scientists require multiple models to achieve scientific goal z. (shrink)

Utilitarianism is one of the most famous ethical doctrines, based on the ideal of maximizing pleasure and minimizing pain. But Utilitarians and their opponents lack a clear scientific and philosophical understanding of its foundations, the measurement and aggregation of utility. This is what The Pursuit of Happiness now offers.

’Tis vain to talk of adding quantities which after the addition will continue to be as distinct as they were before; one man’s happiness will never be another man’s happiness: a gain to one man is no gain to another: you might as well pretend to add 20 apples to 20 pears.