The great religions have had a profound impact on the attitudes of humans toward animals. For example, The Bible (Genesis 1:26 to 28, 1982), states:

Thus, the biblical concept of God’s dominion over man and man’s dominion over animals is still the foundation of the attitudes of many toward human beings and animals (Gatward, 2001). That is why ancient Hebrew writings in the Old Testament give rise to humane treatment of animals (Proverbs 12:10):

The verse refers to how kindness to animals is equated with the legality of righteousness and the very characteristic of God himself. The writer suggests that the individual who behaves in a caring way towards his stock is reflecting an attribute of the Divine. This one verse expresses an important aspect of biblical teaching with regard to the human-animal relationship. The relationship should be based on responsibility, care and use allied to sympathy and kindness (Gatward, 2001). The idea means that, dominion over animals implies responsibility and obligation to them, rather than exploitation alone (Broom, 2003).

There is reference to care for and obligation to domestic animals in a number of biblical commandments (Exodus 20:10):

Other laws in relation to animal welfare explain that cattle should not to be muzzled when threshing cereals (Deuteronomy 25:4), should be allowed to eat when hungry and that a hen laying eggs or young is not to be taken (Deuteronomy 22:6):

In spite of the Jewish and early Christian view that animals had no souls to be respected, it was stated that they should be rescued if trapped, treated if they are hurt and have water and food provided when they are hungry or thirsty (Luke 13:15; 14:15):

In Wade’s (2004) view, the traditional Christian ethic concerning the kind of respect that is due to animals can be summed up as follows: avoid cruelty to animals and treat them with kindness. However, for many people in the past and now, animal lives are not considered sacred, they have no significant right to life and, as they lack reason, animals may be used for human benefit (food, companionship, transport, work, recreation and so on). The architect of this ethic was Thomas Aquinas who argued that cruelty to animals was wrong because it encouraged people to behave in a similarly cruel fashion towards others. In addition, if people practiced pity or compassion towards animals, they would be disposed to do the same towards humans. Aquinas’ theology, which was greatly influenced by Aristotle (384 to 322 BC), has a major flaw in his hierarchical model of creation. Human beings are at the top of the pyramid because they are rational beings (“imago Dei”). Animals are lower down the pyramid since they lack rationality. As lower forms of life, irrational animals were under the dominion of and subject to rational beings. Hence, animals could be killed for food and used for human benefit (Linzey, 1987). Ryder (1989) describes this view as “speciesist”. He explains this as the “arbitrary favouring of one species’ interests over another”. The manner in which human beings relate to animals and take constructive responsibility for them is a fundamental dimension of our relationship with God. Linzey (1996) advocates a Christian ethic of vegetarianism. However, Singer (1975) and many others have affections for animals that do not appear to result in ceasing to eat them. Aquinas’s (1963, 1969) teaching of avoiding cruelty to animals and treating them with kindness, although human centred, has the seeds of the development of a Theo-centric animal ethic whose growth is encouraged by current world attitudes (Wade, 2004).

Concern for the welfare of other animals arose as a system of thought in the Indus Valley Civilization as the religious belief that ancestors return in animal form, and that animals must therefore be treated with the respect due to a human. This belief is exemplified in Jainism, and in several other South East Asian religions. Abandonment of animal sacrifice in Jainism, Hinduism and Buddhism resulted in a substantial dislike of unnecessary destruction of life and widespread vegetarianism. Eastern religions emphasize two aspects of human-animal relationships: non-injury to living beings (ahisma) and a repeated, cyclical embodiment (reincarnation) of all living beings (samsara). Ahisma, a doctrine of non-violence or non-killing is taken from Hindu, Buddhist and Jainist views. Ahisma (Sanskrit) means that all Jains and almost all Buddhists are strict vegetarians. The second concept allows for the souls of people to be reborn as non-human animals, and vice versa. Followers of those religions do not believe in a god as a creator. Buddha taught that it is a sin to kill any living being (Kyokai, 1966) saying that the key to civilization is the spirit of Maitri, friendliness toward all living things (Ryder, 1989). Eastern philosophies emphasize that man is equal to others, for example:

Ch’eng brothers and Chu Hsi (1976) suggest that Hinduism is not as strict concerning ahisma as Jainism or Buddhism. It allows animal sacrifice to a limited extent in religious ceremonies. Proper treatment of animals is considered as the Hindu passes toward salvation. However, for Hindus, there is much emphasis on conduct and the doctrine is a general guide (Broom, 2003). Nowadays Hindus are still taught that the human soul can be reborn into other forms such as insects or mammals. The belief that all life should be respected, because the body is an outer shell for the spirit within, forms the basis of Hinduism, Buddhism and Jainism. Hinduism is the oldest of all Eastern religions. The Vedas, India’s ancient scriptures in which Hinduism has its roots, set out the principle of nonviolence, called Ahimsa. Ahimsa, “non-injury” or the absence of the desire to harm is regarded by Indian thinkers as one of the keystones of their ethics. Hindus generally accept the doctrine of transmigration and rebirth and the complementary belief in karma, or previous acts as the factor that determines the condition into which a being, after a stay in heaven or hell, is reborn in one form or another. The whole process of rebirths is called samsara. This concept allows for the souls of people to be reborn perhaps as animals and vice versa. In karma, the previous life acts as the factor that determines the condition into which a being, after a stay in heaven or hell, is reborn in one form or another. Causing unnecessary pain and death produces bad karma with ill-effects on oneself as a consequence of ill-treatment of others. The Vedas set out the code of sarva-bhuta-hita (devotion to the good of all creatures), which says that people should see the same life in all creatures regardless of their outer dress or bodies. In fact the Vedas go so far as to say that those who cannot understand the principle of life in lesser beings are missing the meaning of life altogether and risk losing their sense of humanity. Killing of an animal is seen as a violation of ahimsa and causes bad karma so vegetarianism is widespread among Hindus. Hinduism is not as strict concerning ahimsa as Jainism or Buddhism as Hindus at many times in history have eaten meat. Hinduism allows animal sacrifice to a limited extend in religious ceremonies. Dada J P Vaswani, Spiritual Head of the Sadhu Vaswani Mission said (Vaswani, 2003):

According to Jain beliefs, the universe was never created, nor will it ever cease to exist. It is eternal but not unchangeable, because it passes through an endless series of cycles. Jains believe that reality is made up of two eternal principles, jiva and ajiva. Jiva consists of an infinite number of identical spiritual units; ajiva (that is, non-jiva) is matter in all its forms and the conditions under which matter exists: time, space, and movement. The whole world is made up of jivas trapped in ajiva; there are jivas in rocks, plants, insects, animals, human beings, spirits, etc. Karma and transmigration keep the jiva trapped in ajiva. The consequence of evil actions is a heavy karma, which weighs the jiva down, forcing it to enter its new life at a lower level in the scale of existence. The consequence of good deeds, on the other hand, is a light karma, which allows the jiva to rise in its next life to a higher level in the scale of existence, where there is less suffering to be endured. The Jain ethic is a direct consequence of the philosophy of soul and karma. Jains are animists, for them, everything natural is living, and all life is sacred. Any kind of harm to any form of life is to be avoided or minimized. Of course, the sustenance of one form of life depends upon the death of another, yet the followers of Jainism are required to limit the taking of life even for survival. Jains are strict vegetarians and practice ahimsa very strictly, they literally will not harm a fly. Some Jains will sweep the path before them and wear gauze masks over their mouths to make sure they will not harm small insects by unintentionally treading them or breathing them in. Jains build refuges and rest houses for old and diseased animals, where they are kept and fed until they die a natural death. The welfare of animals and the continued survival of individuals are considered to be of great value.

Buddhism is a religion and philosophy that developed from the teachings of the Buddha Gautama, who lived in the 6th century BC. Buddha Gautama taught the four noble truths: that there is suffering, that suffering has a cause, that suffering has an end and that there is a path which leads to the end of suffering. In Buddhist teaching, the law of karma, says that for every event that occurs, there will follow another event whose existence was caused by the first, and this second event will be pleasant or unpleasant according as its cause was skilful or unskilful. So Buddhist law says that those who cause violence and suffering to living things will experience that same pain at some time in the future. The Buddhist view on animals is illustrated in the Jakata stories (Buddhist lessons). Buddha is born as different animals in previous births, so killing animals is equated with killing humans. Most Buddhists do not eat farm animals, hence they place high value on a better life and hence to good welfare in animals, including good health. Buddhists should get no companionship from animals, there should be no hunting of animals and many Buddhists buy and release wildlife as a way to reduce suffering.

The Islamic religion teaches that Allah has given people power over animals. Therefore to treat animals in a bad manner is to disobey Allah’s will. They believe that the world belongs to Allah and people are responsible to Him for their behaviour towards animals. As in Christianity and Judaism, it is taught that whatever an individual does will be known to God/Allah. Consequently, it is wrong to hunt merely for pleasure, to use its skin, to cause animals to fight each other, to incite them to act unnaturally, or to molest them unnecessarily. The Prophet Muhammad taught that animals should be killed only out of necessity and that doing otherwise is a sin. In the Qu’ran the creation of certain elements of the animal kingdom is described with the purpose of making humans reflect upon the divine Beneficence they receive. It is quoted to provide an example of the way in which the Qur’an (1997) describes the adaptation of creation to man’s needs (Sura 16, verses 5 to 8):

The Qur’an (1997) underlines that the world has been created for the benefit of man (Sura 2, verse 29):

Islam apparently does not have any doctrine about what happens to animals after their death. The Qur’an (1997) highlights animals’ submission to Allah’s Power (Sura 16, verse 79):

Additionally to the influence of religions on human and animal relationships, the ancient societies of Greece and Rome also played an important role in the formation of attitudes towards animals (Staller, 1995; Broom, 2003). The societies seemed to differ in their views on humans and animals. There were four schools of thought in ancient Greece on human-animal relationships: animism, mechanism, vitalism, and anthropocentrism. Animism’s central personality was Pythagoras (569 to 475 BC) the mathematician stating that animals and people have souls similar in kind. He professed that the souls are indestructible and composed of fire or air, and move from human to animal or human in succeeding incarnations. Vitalism recognized the difference between organic and inorganic entities. Vitalists such as Aristotle (382 to 322 BC) emphasized the interdependence of soul and body (Ryder, 1989). A scale or ladder of nature has been recognized in which higher forms of life shared simple functions with lower forms resulting in complex behaviour. This scheme of continuity could have been combined with the theory of evolution. The view of mechanism professes that humans and animals are mere machines and such as they are essentially the same without soul differentiating them from inanimate matter. Anthropocentrism regarded humankind being in the centre of the world, and existence, welfare, and well-being as the ultimate aim of the universe. Everything in the universe was interpreted in term of humans and their values.

The father of modern philosophy René Descartes (1596–1650) reinforced the separation between humans and animals with the assertion that the body is a machine, and what sets humans apart from the animal machines would be the lack of true speech, reason and feeling pain (Descartes, 1649). In fact, the modern philosophy has been started with the period of enlightenment and renaissance. Friend (1990) reported that Descartes’ followers were known to kick their dogs just to hear the machine creak. At that time vivisection was a common practice when studying how animal organisms work. The eighteenth century was an age of enlightenment as notable figures of that time such as Voltaire (1694 to 1778), Hume (1711 to 1776), and Rousseau (1712 to 1778) questioned the popular idea that animals feel no pain and that they are ours to do with as we please (Singer, 1975). The enlightenment, however, did not affect all thinkers equally in the matter.

Kant (1724 to 1804), in his lectures on ethics, still stated that:

What is Kant saying here? Effectively, Kant is taking the view here that animals have only instrumental value, morally speaking:

So, for instance in vivisectionists’ view

As mentioned above, Singer (1979) objects strenuously to this view.

In the modern period the utilitarianists’ views are discussed at length by Broom (2003). Bentham (1789) in a definitive answer to Kant stated that:

He was perhaps the first Christian philosopher to denounce “men’s dominion” as tyranny rather than legitimate government. The sentence cited is widely quoted by those concerns about animals. Thus, the concept of utilitarianism was first explicitly articulated by Jeremy Bentham (1748–1832) and further developed by John Stuart Mill (1806 to 1873). In deciding whether an action is morally right, the total amount of good the action will bring about is weighed against the total amount of harm that will be caused (Mill, 1863). Singer’s book (1975) on Animal Liberation led to many philosophical conversions. Although a lot of people may think that Singer supports a rights-based view, he bases vegetarian lifestyle on an animal welfarist and a hedonistic utilitarian position rather than on any claim about of killing animals being wrong. He justifies his position with what he calls the replaceability argument stating:

This view mirrors a utilitarian philosophy that if an animal has no sense of the future and lives a relatively contented life, the animal’s premature but humane death is acceptable if it improves the welfare of others and if the animal is replaced.

Simply defined the concept of speciesism (Ryder, 1989), discussed in general terms by (Singer, 1975), is a prejudice or attitude bias in favour of the interest of members of one’s own species and against those of members of another one. In the authors’ view, pain and suffering are bad and should be prevented or minimized, irrespective of the race, sex, or species of the being that suffers.