Spinoza on Animals

Why the rational pursuit of human advantage permits, and limits, our treatment of non-human beings

I. The Difficult Passage

Ethics, Part IV, Proposition 37, Scholium 1 contains Spinoza's most extended comment on animals. "It is plain that the law against killing animals is based more on vain superstition and womanish pity than on sound reason. The rational quest of what is useful to us teaches us the necessity of associating ourselves with other men, but not with beasts, or things whose nature is different from human nature. We have the same right against them that they have against us. Indeed, because the right of each thing is defined by its virtue or power, men have a far greater right against beasts than beasts have against men."

The passage disturbs modern readers. It seems to justify cruelty. It dismisses compassion as "womanish pity." It reduces the moral status of animals to a calculation of power. A superficial reading concludes that Spinoza is simply endorsing the exploitation of animals for human benefit. The superficial reading is, as usual, inadequate.

II. The Framework

Spinoza's treatment of animals follows directly from his metaphysics. All things, including animals, are modes of the one substance. They have conatus: the drive to persist in their being and increase their power. They have rights in Spinoza's specific sense: the right of each thing extends as far as its power extends. A lion has the right to eat a gazelle because it has the power to do so. A human has the right to use animals for his purposes because he has the power to do so. This is not a moral claim. It is a factual description of how power operates in nature. Rights are not moral entitlements. They are extensions of power.

But this framework does not license cruelty. It licenses use. The distinction is crucial. The rational person, Spinoza argues, seeks what is useful to him. What is useful is what increases his power to act. Cruelty: the infliction of suffering for its own sake or for trivial benefit: does not increase human power. It diminishes it. The person who is cruel to animals is governed by passive affects: the pleasure of domination, the excitement of causing pain, the need to feel powerful by making something else powerless. These affects are signs of bondage, not freedom. The free man, governed by reason, does not act cruelly, not because animals have rights that constrain him, but because cruelty is an inadequate affect that diminishes his own power.

III. The Limits of Association

Spinoza's stronger claim is that humans should associate with other humans but not with animals, because animals do not share human nature. This claim requires careful examination. Spinoza is not saying that humans and animals have nothing in common. They are all modes of the same substance. They all have bodies and minds. They all strive to persist. But they differ in the complexity of their bodies and therefore in the complexity of their minds. Human beings, because of the complexity of their bodies, are capable of reason, of forming adequate ideas, of participating in the intellectual love of God. Animals, with less complex bodies, are less capable of these things.

The practical consequence is that the highest form of association: friendship grounded in shared understanding and the mutual increase of power: is not available between humans and animals. You can love a dog, but the dog cannot understand you in the way another human can. The dog's love is real, but it is love in the inadequate sense: joy accompanied by the idea of you as an external cause. It is not the love grounded in shared understanding that Spinoza describes as the highest form of human relationship. This is not contempt for animals. It is an accurate description of the difference between human and animal minds. The difference matters. It means that the deepest forms of human flourishing require association with other humans, not with animals. The person who substitutes animal companionship for human companionship is depriving himself of something essential.

IV. The Modern Extension

Spinoza's framework, extended to modern knowledge, supports stronger protections for animals than Spinoza himself would have endorsed. Modern biology has demonstrated that many animals are far more complex than Spinoza imagined. They have rich emotional lives, complex social structures, and in some cases something approaching rudimentary reason. The difference between human and animal minds is a difference of degree, not of kind. Spinoza's framework, which grounds moral consideration in the complexity of the body and mind, would require that we adjust our treatment of animals as our understanding of their complexity increases. The rational use of animals for human benefit must take account of their actual nature, not the simplified nature that seventeenth-century biology attributed to them.

The Spinozan position, updated, is this. The use of animals for human purposes is not inherently wrong. We are part of nature, and predation is part of nature. But the use must be rational, not cruel. It must genuinely increase human power rather than merely gratifying passive affects. Factory farming, which produces vast suffering for trivial benefits, fails this test. It is not rational use. It is cruelty driven by economic efficiency, and economic efficiency is not an adequate justification for the production of suffering on that scale. The Spinozan, while rejecting the sentimental elevation of animals to the status of persons, would also reject the industrial reduction of animals to the status of machines. Both positions are inadequate. The adequate position recognizes the real differences between humans and animals while also recognizing the real complexity and capacity for suffering that animals possess. The recognition of complexity generates obligations. The obligations are not based on rights but on the rational pursuit of one's own power. A person who participates in the systematic production of suffering diminishes his own capacity for adequate understanding. The diminution is the real cost. The suffering is real too, but the suffering of animals is not the primary reason to avoid cruelty. The primary reason is that cruelty corrupts the person who practices it. Spinoza would have understood this, even if he did not say it.