Peter Singer’s book remains as significant today as when it was first published back in 1975. Celebrated as the ‘bible’ of the animal rights and animal welfare movement, it was instrumental in getting a whole generation of activists on their feet and triggering a compassionate revolution. It challenged preconceptions and sparked widespread, global debate and discussion. It presented a strong argument for the equality of non-human animals, and advocated vegetarianism as a benefit to the lives of both humans and non-humans.

Singer popularised the term ‘speciesism’. He argued that speciesism is in exactly the same realm as sexism and racism: “Speciesism…is a prejudice or attitude of bias in favor of the interests of members of one’s own species and against those of members of other species. It should be obvious that the fundamental objections to racism and sexism made by Thomas Jefferson and Sojourner Truth apply equally to speciesism. If possessing a higher degree of intelligence does not entitle one human to use another for his own ends, how can it entitle humans to exploit nonhumans for the same purpose?”

In the UK and around the world animals are still considered by the majority as ‘commodities’ – alive only for the purpose of human pleasure, entertainment, consumption or use, rather than as sentient beings in their own right who are able to feel, suffer and perceive. A great deal of ignorance remains about the conditions and treatment of animals in laboratories or on factory farms, despite the best efforts of animal welfare groups to expose these. It continually surprises me that, for example, people aren’t aware of issues such as the fact that dogs and cats are regularly eaten in parts of Asia, particularly China and Vietnam; that cows and pigs in the UK are kept in stalls and never given access to graze in the fields; that cosmetics purchased in the UK can be still tested on animals… There is still a long way to go before the practices Singer details in Animal Liberation come to an end.

Animal Liberation leads its readers on a personal journey of discovery. Even reading it now, as a seasoned campaigner, I find that it manages to challenge my understanding and perceptions. I, too, am culpable, complicit in the continued suffering endured by animals, I discover – albeit against my will – in the taxes I pay, for example, which still fund much of the same scientific research, Ministry of Defence tests, and farmer subsidies that Singer recorded over three decades ago.

Of course, some conditions for some animals have improved. There has been a drive to re-acquaint the public with the source of its meals, to raise consciousness, to inform us of the awful conditions endured by intensively farmed animals. New EU legislation means that since January 2012 no laying hens should be being kept in tiny, barren cages. (Some countries are not, of course, ‘ready’ to implement these vital changes, and are scrabbling around for loopholes.) In 2006 the UK government revised outdated animal laws to produce an Animal Welfare Act. The Act enables intervention in cruelty cases, whereas previously prosecution could only take place once the cruelty and suffering had happened. The UK has banned fox hunting. And all bar a few supermarkets have agreed to the principle, at least, of installing CCTV cameras in their abattoirs.

In countries around the world the animal welfare movement is growing and discussion and debate are happening, not least of all in China. Year on year Chinese animal welfare groups are being established to fight for the rights of animals. Despite the odds, many people are finding their voices and are calling for laws to protect animals.

But there’s still a long way to go.

Perhaps the most important consequence of Peter Singer’s Animal Liberation is that it ignited a debate on the use and abuse of animals that is still thriving today. It helped mobilise, and underpin, a whole animal protection movement.

Only through exposing the suffering of animals will we bring about change. As consumers and taxpayers we all have a role to play in shaping the world in which we want to live. Apathy is perhaps our biggest challenge. With busy lives it is easy to excuse ourselves and not to act. Change requires determination and commitment; organisations and individuals uniting together to end this terrible exploitation and to nurture respect for animals.

Together we can make a difference! And almost 40 years on, Peter Singer’s timeless classic is still as motivating as ever.

Gill Maltby is the UK Director of Animals Asia Foundation and a long-time animal welfare campaigner.

It sounds ironic that the animal rights movement has benefited greatly from a book by an author who doesn’t even like the term ‘animal rights’. However, Singer is an animal rights advocate himself – and one of the most effective ones.

The difference between animal welfarists and animal rights campaigners is that the former aim to minimise the suffering that is caused by animal exploitation, whereas the latter intend to stop the exploitation altogether.

Before the publication of Animal Liberation, there were very few animal rights campaigners, partly because there was very little awareness of the scale of animal suffering taking place behind closed doors, particularly in vivisection laboratories and factory farms. Chapters 2 and 3 of Animal Liberation told people precisely what was happening. And it made for shocking reading.

The number of initial readers was not massive but some of those readers went on to influence many others. Jean Pink read the book, quit her job as a teacher and founded Animal Aid, which helped create the modern animal rights movement. There are, of course, other examples. The book was a major catalyst.

In the Preface, Singer demolishes the argument that human suffering is more important than animal suffering, and that it is therefore sentimental to be campaigning for animals while human suffering still exists. He states: “No matter what the nature of the being, the principle of equality requires that its suffering be counted equally with the like suffering – insofar as rough comparisons can be made – of any other being.” He argues that it is speciesist to say that people are more important just because of their membership of the human species, just as it is racist, sexist or homophobic to argue that one group of people is more important than another.

Singer has his detractors because he is not keen on the idea of animal ‘rights’. We should remember that this is because he is not keen on the idea of rights per se – not because he thinks they are for humans only. His philosophy is utilitarianism: the belief that we should maximise overall pleasure, and minimise overall suffering. Other utilitarian philosophers only applied this principle to people; Singer exposed the weakness of that position.

So there is nothing speciesist about Singer’s utilitarianism, but nonetheless it can still cause problems from an animal rights perspective. Utilitarianism could be used to justify, for example, painful and fatal experiments on ten mice if the research would thereby save thousands of people from developing a painful terminal illness. However, the justification would be due to the comparative amounts of suffering caused and prevented – not due to the difference in species.

However, Singer doesn’t give the unequivocal moral condemnation of animal experiments that so many humane people are looking for, so why bother with him when one can read others (Tom Regan, for example), who are absolutely sound on animal rights? To my mind, no one else is as persuasive as Singer. He is a campaigner as well as a philosopher (as is more than clear in his 2006 book In Defense of Animals: The Second Wave).

In Animal Liberation, he discusses the strategies needed to encourage people to give up meat and other animal produce. Thirty-seven years after the first edition was published, I believe that Animal Liberation is still the book that animals most need everyone to read.

Richard Mountford is the Development Manager for Animal Aid, a longstanding animal rights campaigner and a keen reader of Peter Singer’s works.