Some ethical theories: 

Duty or rule-based / deontological ethics

At least some acts are morally obligatory regardless of their consequences for human welfare, e g, “Duty for duty's sake,” “Virtue is its own reward,” and “Let justice be done though the heavens fall.”

-       Kantian: universalisable - act only according to that maxim by which you can also will that it would become a universal law; act in such a way that you always treat humanity, never simply as a means, but always at the same time as an end

-       Divine command theory: most religions have a version, e g the 10 commandments...

Utilitarianism: determines right from wrong by focusing on outcomes, consequences. Utilitarianism holds that the most ethical choice is the one that will produce the greatest good or greatest happiness for the greatest number. Variations: Rule Utilitarianism; Negative Utilitarianism.

Utilitarian Jeremy Bentham (1789): “The question is not, Can they reason?, nor Can they talk? but, Can they suffer? Why should the law refuse its protection to any sensitive being?”

Existentialism: the philosophical belief we are each responsible for creating purpose or meaning in our own lives. Our individual purpose and meaning is not given to us by Gods, governments, teachers or other authorities.

Intuitionism: the belief that there are objective moral truths in life and that human beings can understand these truths intuitively.

Virtue ethics: an action is only right if it is an action that a virtuous person would carry out in the same circumstances; a virtuous person is a person who acts virtuously; a person acts virtuously if they "possess and live the virtues needed to live well”.

Sentientism: grants moral consideration to all sentient beings, not just humans, sentience being the capacity to experience suffering and flourishing. 


So, why - and how much - should we care about other animals? Questions for discussion:

- Pros and cons
of each theory and application to other animals?

- Can we extend values such as human rights to other animals? How like/unlike us are they re consciousness, pain, suffering, death? Does that matter (cf Bentham)?

- Where do we draw the line: fish? slugs? insects? limpets? Is it wrong to kill a mosquito? Is it wrong to eat road kill?

- What about the cruelty of nature, short lives, animals killing each other, often painfully?

- Environmental/sustainability issues arising from meat consumption? Deforestation, methane emissions? Pollution... Or is this just us caring about ourselves?



Further reading

Mary Midgley Animals and Why They Matter

Peter Singer Practical Ethics &  Animal Liberation + an interview in The Observer, 215/23  

Peter Singer on Non-Human Animal Ethics at

Julian Baggini The Pig that Wants to be Eaten and 99 other thought experiments; Ethics The Big Questions

Simon Blackburn Ethics A Very Short Introduction

Nigel Warburton Philosophy The Basics