Aquinas

University of Naples, 6 December 1273. A Dominican friar and scholar is working on the final section of his life's culminating work. He is about 48 years old, and has written many biblical and philosophical commentaries and theological treatises. He goes to celebrate mass, and there he experiences a crisis – a mystical experience, or possibly a stroke. "All I have written seems as straw compared to what I have experienced," he says, and he abandons his masterpiece unfinished. A few months later, he falls ill on a journey to a church council in Lyons, and he dies at the monastery at Fossanova on 7 March 1274. The man is Thomas d'Aquino, known to us as Aquinas, and the work is his Summa Theologiae.
The 13th century was a turbulent era of crusades, religious conflicts and power struggles. Two of Aquinas's brothers were caught up in wars between Emperor Frederick II and the papacy, and one was executed for treason. Wars were fought in the name of religion, such as the fourth crusade and the Albigensian crusade. However, it was also one of the most exciting intellectual eras in European history.
Learning had shifted from monasteries and cathedral schools into the newly established universities. Muslim scholars had brought Arabic translations of Greek texts into the west, and their subsequent translation into Latin introduced Christian scholars to the works of Aristotle and others. Christian doctrine was encountering a wide range of competing beliefs, including those of Greek philosophy and its Jewish and Muslim interpreters. Aquinas brought to that era a synthesising brilliance with regard to texts and ideas which has left a deep imprint on western religion, politics, law and ethics.
Unlike his warring brothers, Aquinas was happier reflecting upon life than immersing himself within it. It was ideas, not politics and current affairs, that captured his imagination. As a young man he defied his family's wishes that he should enter the Benedictine order, opting instead to join the recently established Dominicans or Order of Preachers, which he had encountered during his studies in Naples in 1242-43. His family arranged for him to be kidnapped and imprisoned and they even sent a prostitute to seduce him (nobody explains why seduction by a prostitute might make him more inclined to join the Benedictines than the Dominicans). Aquinas resisted and eventually his family capitulated.
GK Chesterton described him as "a huge heavy bull of a man, fat and slow and quiet, very mild and magnanimous but not very sociable". His fellow friars referred to him as "the dumb ox", to which his teacher Albert the Great responded that "the dumb ox will bellow so loud that his bellowing will fill the world". Aquinas was a man of profound humility and prayerful contemplation, but he was also a pioneering genius whose writings constitute the apotheosis of medieval thought and the embryonic beginnings of modernity.
Aquinas's apparent indifference to the crusades and his pragmatism with regard to violence and suffering might shock modern sensibilities. However, our own era is also divided between violent conflicts and great intellectual achievements,

and there are many scholars who show little interest in war and politics, and yet who produce works of scientific, philosophical and artistic genius. In detaching himself from the turmoil surrounding him, Aquinas was able to dedicate himself to his life's mission.
Through a close engagement with Aristotelian philosophy, he wanted to demonstrate that faith and reason, philosophy and theology, could be united in a mutually beneficial marriage within the overarching goodness of a cosmos created, ordered and sustained in all its aspects by God. Like all marriages of Aquinas's time, this was not a partnership of equals, for philosophy was theology's handmaid. Ultimately however, faith and reason, grace and nature, went together like love and marriage or horse and carriage, and together they could guide the human mind in its desire for God and for truthful knowledge about the world.
A number of obstacles must be overcome if we are to appreciate Aquinas today. In Protestant cultures he remains associated with an era that many believe to have been mired in barbarism and superstition, notwithstanding the magnificence of the medieval legacy, from the great cathedrals of Europe to the rise of the universities. The influence of modern scientific atheism has led to the widespread belief that one must choose between faith and reason, and that faith is fundamentally irrational and opposed to science. This is an idea that Aquinas dedicated his life to resisting. If we can set aside our prejudices in order to approach him afresh, we may be surprised at how relevant he still is.
In his influential book, A Secular Age, philosopher Charles Taylor contrasts the "porous self" of the Middle Ages with the "buffered self" of modernity. Aquinas can be seen as a figure who stands between these two worlds.
Taylor argues that our medieval ancestors inhabited an enchanted universe that was alive with magical powers. The boundary between the individual human and the rest of nature was porous, and humankind belonged within a vast organic cosmos of seen and unseen beings. This helps us to understand why Aquinas regards angels and demons as real creatures who invite philosophical reflection as much as any other life form.
Modern rationalism sealed off the mind from such ideas, eradicating the hidden forces of nature and subduing the power of the imagination. But it was Aquinas and his scholastic contemporaries who set in motion this transformation in the order of western knowledge, when they married philosophy to theology. Aquinas might have been appalled to know that eventually the scaffolding of reason would no longer rest on the bedrock of faith, but he played a significant role in erecting that scaffolding. That is why, despite his medieval context, we might acknowledge him as a father of modernity.
Aquinas's understanding of the human soul was very different from our modern concept of the mind. It was perhaps closer to the Freudian idea of the soul. Freud was an atheist, but in German his work refers to the soul (seele), wrongly translated into English as "mind".

The mind, or soul, that psychoanalysis reveals tells us that our unconscious is home to the fantasies, desires and terrors of a more primordial self, so that a turbulent otherness seethes within the ostensibly rational and autonomous mind of scientific modernity. We need only think of computer-generated creatures to realise that angels, demons, gargoyles and monsters retain their ability to fascinate and terrify us. So maybe the differences between Aquinas's world and our own are not that great, if we expand what we mean by "the mind".
Nature, including human nature, is for Aquinas essentially good because existence itself is good. He said repeatedly that "grace perfects nature" – our desire for God makes us more, not less, natural. A more pessimistic view emerged when the theologians of the reformation set grace over and against nature, insisting that the goodness of human nature had been entirely destroyed by original sin. This paved the way for the Enlightenment and the scientific revolution when nature, including human nature, was finally subjugated to the control of the rational mind, severed from its scriptural and theological inheritance.
For Aquinas, reason is natural to our species, because it is what a creature needs if it has choice. Other animals, lacking freedom, naturally do what is good for them according to the kind of species they are. They too have souls, but the human is uniquely endowed with intellect and will because we are made in the image of God and therefore enjoying a relative freedom in relation to the world. Our intellect enables us to imagine the world as other than it is, and to weigh up the choices which present themselves to reason through our senses and experiences.
Intellect, will, and reason, all have precise, technical meanings for Aquinas.
Reason is the natural activity by way of which we organise and conceptualise these experiences, but the intellect enables us to discern the truth within them. It is the intellect that transforms knowledge into wisdom as we are drawn to the goodness and beauty of God by the diverse goods of the world, and enables us to choose those goods that best express our desire for the ultimate good.
Our will directs our activities so that we can act on these insights. This has an important consequence. For Aquinas the will is about love and desire, not about power and control. The modern concept of willpower emerged when "man" set reason against nature and began to use his will as an expression of control, rather than of desire in relation to the things of the world.
But our desire is influenced by sin, so that we are vulnerable to addictive cravings which destroy our freedom and our capacity for happiness. The good life therefore requires us to discipline desire if we are to be truly free and happy. But it's important to realise that Aquinas does not think we can be motivated by evil. We can be mistaken – innocently or even culpably – in what we think would be good for us, but we cannot be motivated by evil, because evil cannot be more than an absence of the good.

Aquinas is first and foremost a reasoned Christian optimist. Life is very good, because all beings participate in God's being. As one scholar writes, "the being of God is the doing of the world". We'll start from there next week.
Thomas Aquinas would have agreed with a comment on this website that he was as vulnerable to error as anyone else and should never be taken as "the truth". He has read widely and deeply: Aristotle's influence is evident throughout the Summa Theologica, as is that of St Augustine. Other philosophical influences include the pagan (Plato and the Stoics, Dionysius and Boethius), the Muslim (Ibn Rushd,aka Averroes, and Ibn Sina, aka Avicenna); and the Jewish (Maimonides). But Aquinas argues that theological first principles derive from scripture, which is the ultimate authority for Christian doctrine. All other thinkers, however great, must be measured against the biblical authors.
This does not make Aquinas a biblical literalist. He argues that the Bible is written in metaphors that render the divine mystery meaningful for finite human minds. We depend on material objects for our knowledge, and therefore we can only speak of God as if God, too, were part of the material world. Biblical language is multilayered, opening itself to mystery the more one allows its meanings to unfold. Aquinas says of scripture that "the manner of its speech transcends every science, because in one and the same sentence, while it describes a fact, it reveals a mystery" (ST I.1.10). Anyone who has ever thrilled to poetry understands this. Profound truths speak to us through ordinary metaphors when we take time to listen and reflect. Indeed, Aquinas insists that we should avoid exalted imagery when we speak about God, in case we are deceived into taking our language too literally.
Aquinas's scriptural fidelity must be held alongside his conviction that there is no contradiction between revelation and reason, because the author of nature is the same God revealed in scripture. If the one appears to contradict the other, then we are mistaken either in our interpretation of scripture or in our science. So, given the scientific evidence for evolution by natural selection, he would say that creationist Christians are wrong in the way they interpret the Bible. Moreover, "faith presupposes natural knowledge, even as grace presupposes nature" (ST I.2.3). We depend on nature to bring us to faith. To accept revealed truth does not mean going against reason but going beyond the reach of reason to allow the mind to rest in mystery.
It is unfortunate that Aquinas's five proofs for the existence of God are part of every philosophy of religion course, because they are not central to his thought. He does not set out to prove that the existence of God is a logical necessity, but to show that it is a rational proposition. Nor does he intend to persuade those who have closed their minds to the mystery of God within creation, for they will not be persuaded by argument. The five proofs are mainly to prevent theologians from making fools of themselves by claiming either too much or too little knowledge. They can be seen as grammatical rules intended to govern theological language while safeguarding the mystery of God.

Aquinas insists that "what God is not, is clearer to us than what God is" (ST I.1.9.3). If one has to speak of the existence of God without appealing to revelation, then Greek philosophy provides the means to do so with its idea of an unmoved mover, an uncaused cause, a necessary being to account for contingent beings, a transcendent source of reality and goodness to explain our awareness of reality and goodness in the world, and an intelligent first principle that orders the world in such a way that we can understand it. In other words: being has an origin and a purpose, and that is God's being.
We must, however, avoid any suggestion that God is a being like other beings, only more perfect. That is like saying that Mozart must have been a perfect symphony, because his symphonies are so sublime. Aquinas might say that we know no more of God through creation than we know of Mozart through his music. We can only allow our wonder to be awakened by the beauty of what has been created. The being of God is better understood as a verb than a noun. It is the dynamism of being that sustains all beings, so that were God to cease the activity of holding creation in being, "all nature would collapse" (ST I.104.1). We could say that God's being is what God does, most perfectly expressed for Aquinas in the words "I am who I am" (Exodus 3:14). This is what Aquinas means by God as "pure act" (actus purus). It is a simplicity of being beyond all the complexity of matter and form, body and soul, potency and act, which constitutes the universe of created beings. Let's start there next week.
One question has captivated the human imagination from the pre-Socratic Greeks to scientists working at Cern: how did the world begin? To understand how Thomas Aquinas approaches this question, we need to recall the influence of both Aristotle and Plato on his thought – the former through years of immersion in his writings, the latter through limited access to Plato's works (primarily the Timaeus), mediated by way of Christian neo-Platonists.
Aristotle credits Parmenides with the idea that nature abhors a vacuum, an idea with a lasting influence on western thought. Nothing comes from nothing, so what was there before there was anything? This leads to the proposition that the universe exists eternally, and the theory of form and matter is a way of explaining this. At either end of the spectrum of existence there are two eternal opposites – unformed matter and immaterial form – which are the precondition for everything that exists. Plato and Aristotle agree on this, but they offer different interpretations.
Plato's cosmos is a hierarchical chain of being emanating from and returning to the Good, which is the highest form and the ultimate principle of being. The relationship between form and matter is one of transcendent ideas and material appearances that dimly reflect the forms. The human mind is equipped with innate ideas – think of a new computer with the software already installed – and this enables us to discern the forms beyond the material appearances we encounter in the world.
Aristotle argues against Plato for a more dynamic and interactive understanding of being and knowing. There is no innate knowledge, and the human mind

cannot possibly know matter or forms except together in animate or inanimate objects. Aristotle sees movement, and cause and effect, as the fundamental principles by way of which form and matter conjoin. There is a prime mover – an impersonal intellect – that originates the movement by way of which forms animate matter in a continuous process of birth, growth, reproduction and decay. Aristotle's prime mover is not a first cause but a final cause, a kind of magnetic attraction drawing all beings towards their natural telos or end. This attributes a purpose to existence: every natural species, including the human, flourishes most fully when it conforms to the end for which it exists.
Aquinas attempts – successfully? I'm not convinced – to combine Aristotelian and Platonic cosmologies within his biblical understanding of creation. God creates time and space, form and matter out of nothing, and the God of Greek philosophy becomes the personal trinitarian God of Christian theology. But what about Genesis?
In Aquinas's time, some philosophers, especially those influenced by the Islamic philosopher Averroes, accepted the idea of an eternal universe, but Genesis commits Aquinas to defending the origin of the world created by God. However, he is emphatic about the need to distinguish between revelation and reason in making such claims:
"That the world began to exist is an object of faith, but not of demonstration or science. And it is useful to consider this, lest anyone, presuming to demonstrate what is of faith, should bring forward reasons that are not cogent, so as to give occasion to unbelievers to laugh, thinking that on such grounds we believe things that are of faith." (Summa theologiae I.46.2)
Scientists today still argue about what, if anything, was before the big bang. Those who say that it simply happened out of nothing are not far from Aquinas. If God is outside time and space, our temporal and spatial concepts are too limited to know what that means, and it's certainly nothing we can meaningfully speak of.
Aquinas believed that Genesis was factual, but this is relatively unimportant. Today we live in a flattened universe, insofar as we see facts and nothing more. The medieval world was impregnated with symbolic meanings, which included texts as well as natural objects. We can read Genesis as a myth of origins (it has some resonances with Freud as well as Darwin), but there are three essential truths that Aquinas would say Christians cannot dispense with: God creates a good world, humans are made in the image of God, and something has gone wrong with our human way of being in the world. More about all that next week, but let me end with a slightly different myth of origins:
"Once upon a time, 3 billion years ago, there lived a single organism called LUCA. It was enormous: a mega-organism like none seen since, it filled the planet's oceans before splitting into three and giving birth to the ancestors of all living things on Earth today." (New Scientist, 26 November 2011).
Scientists also communicate in myths and metaphors. That's part of what it means to be a human being and not a computer.

For Thomas Aquinas, the human is a paradox. As "rational animals", we are the only species that straddles the divide between matter and spirit. We do not just inhabit the material world – we interpret it, discern order within it, derive meaning from it and act decisively upon it. Our intellects transcend their material confines with a unique freedom and imagination.
Today, this is referred to as the problem of consciousness. How did a species jump the evolutionary tracks and acquire a capacity to reflect upon its existence within a world of which it is a part and to whose laws it is subject? Questions like this are fundamental to our understanding of what it means to be human.
Following thinkers such as René Descartes and Immanuel Kant, modern philosophers tend to think of our rational minds imposing meaning on the world. Aquinas understands this process in reverse. We absorb knowledge first through our senses, and the intellect gradually develops through our bodily experiences and desires. In this, Aquinas is closer to David Hume than to Kant. Beautiful things arouse our desire, which leads to the formation of concepts, the awakening of understanding and the attribution of meaning. Enriched with a deeper appreciation of the source of beauty and goodness, understanding is transformed into love and our desire pivots back towards objects in order to express this love. Love, knowledge and goodness are inseparable. The goodness we perceive derives from the fact that created beings participate in the goodness and love of God. This explains the order and beauty of nature and our response to it.
For Aquinas, our desire for God is the link between consciousness and matter. God is the living, intelligent medium in which bodies and souls are drawn to one another in a coherent and orderly universe. We could say desire is the current that creates invisible connections among beings within the being of God. Matter acquires form and flows towards God in all the diversity of creation as different life forms emerge. This means that to be good is to flourish and fulfil one's potential as a particular kind of being. Just as a washing machine is good when it does what it was designed to do, so a human is good when he or she lives as humans are created to live. This is a more inclusive concept of the good than morality alone. Morality plays a significant part, but for Aquinas there is more to the good life than being moral.
Aquinas uses Aristotle to explain all this philosophically, but from a doctrinal perspective the human made in the image of God relates to the Christian understanding of the Trinity. All desire is orientated towards the trinitarian God, in whose image we are made and to whom we are attracted as the ultimate purpose and meaning of our lives. God is a unity of three persons in an inexpressible relationship of generative, communicative and creative love, and the human soul manifests that in its capacity to understand, interpret and love the world. Rational reflection assists us in this task, but reason alone cannot make us act. Our reason must inform our will, which in turn enables us to materialise our desires by directing our actions towards their intended effects.

So, in our understanding, loving and communicating we express something of the life of the Trinity.
However, our desire also suffers from distortion and deception. We mistake the nature of the good and succumb to obsessions and addictions which enslave us. If we are to live well and to be truly free, we must understand and discipline our desires, in order to liberate ourselves from their potentially distracting and destructive influences.
Sin is an unpopular word today and Aquinas would have said it might be better to find a different word. Whatever we call it, his understanding of distorted desire (concupiscence) might offer some psychological insight into why consumerism is such a destructive ideology. A certain kind of atheism and a certain kind of consumerism might even go hand in hand. The more we deny our most fundamental desire for beauty and goodness that Aquinas calls God, the more insatiable our appetites become. When we fail to realise that our deepest desire is for something that this world cannot offer, that our thirst for knowledge can never be satisfied by science alone, we risk becoming endlessly frustrated and restless in our proliferating desires to possess and control everything around us. To quote the Rolling Stones: "I can't get no satisfaction, 'cause I try and I try and I try and I try." Aquinas would say that our desire draws us towards a source of joy beyond the horizon of this mortal life, and only in accepting that are we free to know and enjoy the things of creation in a balanced and harmonious way.
Thomas Aquinas's Aristotelian interpretation of natural law has shaped western law and politics, although it is a minor section in the Summa Theologiae (ST II.I.94). It belongs within a comprehensive account of four levels of law (ST II.I.90-104). Eternal law is incomprehensible to us, because it is the order upon which all other order depends. We cannot think outside the laws we think with. Divine law is revealed in scripture and is meaningful only to those who accept scriptural authority. Natural law is what we have in common. It refers to our rational capacity to discern general principles in the order of nature to enable us to flourish as a species in communities, given that by nature we are social animals. Today, we might say that it is in our DNA.
Human law is the interpretation of natural law in different contexts (ST II.I.95- 97). Like Aristotle, Aquinas believed that just laws relate to the species, so the collective good comes before the individual good – although in a just society, these are not in conflict. This means that law is not about individual morality, and individual vices should only be legislated against when they threaten harm to others. Unlike Aristotle, Aquinas believed that an informed conscience takes precedence over law. No individual should obey a law that he or she believes to be unjust, because laws that violate reason are not laws. Moreover, laws must have sufficient flexibility to be waived when necessary in the interests of the common good.
Natural law supports different cultures and religions, but unjust societies are those whose laws violate natural law.

Modern thinkers who appeal to natural law as a foundation for morality often lose sight of Aquinas's naturalism, presenting it as a transcendent rational capacity or divine command that overrides our natural instincts and desires. This manifests itself in the rationalist quest to conquer nature (now redounding on us in a looming environmental catastrophe), and in the Catholic church's attempt to use politics and law to impose its views on sexuality over and against changing social customs.
Aquinas argues that laws should change to reflect customs (although custom cannot change natural or divine law). I'll focus on two issues relating to this in terms of a widening gulf between the Catholic hierarchy and modern culture, including many Catholics.
Contraception: Aquinas believed that the sex act must be intended for procreation for the preservation of the species (ST II.II.153.2). He also believed that children need to be raised in a loving environment, and marriage is the proper context for this. But we now know that females are not always fertile, and sexual activity among animals seems to be less functional than he realised. The changing role of women is also a transformation in culture and custom that requires a radical rethinking of law and reproductive ethics. The prohibition of artificial birth control finds little support from this reading of natural law, particularly since it flies in the face of customary practice among many Catholics and non-Catholics.
Homosexuality: once one accepts that non-procreative, loving sex is good, the argument from natural law against homosexuality becomes untenable. What remains central from a Thomist perspective is what it means to live well as a sexual creature whose relationships reflect the love of God and respect the dignity of the human made in the image of God.
Natural law is our rational capacity to interpret the laws of nature in order to use our scientific knowledge well. It is still relevant, even if our science is very different from Aquinas's, as we see from debates about the ethical implications of the laws of evolution. The Darwinian eugenicists of the early 20th century were engaged in one kind of natural law deriving from evolutionary science, and debates on this blog about genetic altruism are another form of natural law. They follow Aquinas insofar as they express a desire to discern order and goodness rather than randomness and futility in what science reveals to us about nature. Evolutionary eugenics may be as rationally defensible as evolutionary altruism, so why do we think one is bad and the other is good? Aquinas would have said because one respects the dignity of the human made in the image of God and the other violates it, but without that perspective, the answer is less clear.
The problem of evil continues to generate a vast literature, but for Aquinas evil is not the insurmountable problem that it is for many modern thinkers. It is simply part of the way the world is. This discussion refers to Summa Theologiae I.49.

Aquinas understands evil in Aristotelian terms of potency and act, cause and effect, lack and perfection, in a teleological context wherein every form of existence has a meaning and purpose particular to its own good. Evil can be explained in metaphysical, natural or moral terms, but it always implies not just the absence of some good but the absence of a good that properly belongs to a species. It is not bad for a human to lack the strength of a lion, for example.
Existence is good, so evil does not exist except as the lack or deprivation of some good that a being should have. We can therefore only recognise evil in the context of a prior understanding of the good of any being. If evil were completely annihilating of the good then it would have to annihilate itself because it depends upon the good of existence to manifest itself as lack.
From a metaphysical perspective, Aquinas asserts that the world is better for having evil within it, because evil serves a greater good. Natural evil contributes to the goodness of creation, and God sometimes inflicts evil as punishment in order to maintain the just order of the universe. Lions kill asses, fire consumes air, humans learn to right wrongs and to endure suffering, and all this is natural and good. However, the projection of morality on to God is a development of modern theism and of the philosophical shift from a naturalistic to a metaphysical account of reason. For Aquinas, God's goodness is beyond all definitions of the good, and we cannot hold God to account by our moral standards. Of course the world could be other than it is, but that would be a different world, and this is the world God created.
From a natural perspective, evil can be unrealised potential, or the unintentional deprivation of some potential that is proper to a species. A baby's inability to walk is bad insofar as she is only potentially a fully developed human, but if she has some disability that prevents her from walking then that is bad because she lacks an ability that is good for the human species. This is different from, say, the potential to become a great musician, which would be a potency and lack only in those humans with an aptitude to become musicians, but not in the generic sense of what is required to actualise one's human potential.
Moral evil results when a person intentionally does something or fails to do something that prevents herself or somebody else from realising their human potential, and it is caused by a defect of the will, that is, by a lack of understanding of the good. Aquinas does not believe that we can rationally desire evil because we can only desire that which exists. Immorality results when we knowingly pursue something that is good in itself but bad for us in terms of what it means to be human. Such acts are liable to punishment by God, and to punishment under the law when they threaten the common good of society.
Some might accuse Aquinas of Panglossian optimism, others of maintaining a punitive or tyrannical view of God. However, let me ask what happens if we apply his understanding of evil as lack to one of the most catastrophic of all moral failures. Could the Holocaust ever be understood only in terms of lack?

The concentration camps were the most extreme example of the wilful deprivation of all the goods humans need to be human: not just the material basics, but dignity, community, love, trust, law and life itself. If we say that this was more than deprivation, that it was caused by the active presence of evil, do we not reduce human responsibility? Aquinas's understanding of morality makes us absolutely responsible for our intentional activities and it allows no excuse in terms of an evil force manipulating our wills. Unless we are suffering from some lack or defect of our natural rational faculties that diminishes our responsibility, we are accountable for what we intentionally do or fail to do. This is still a fundamental criterion of the way the law operates.
When faced with the genocidal horrors of the 20th century, many might find this account of evil as lack deeply problematic. Yet in refusing to situate the power of moral evil anywhere except in the human will, Aquinas's view of morality confronts us with the question that was asked by Rabbi Eliezer Berkovits: not where was God in Auschwitz, but where was man?
Why read Thomas Aquinas? For Catholics and those interested in theology the answer is obvious, but his influence extends beyond that. He was one of the greatest medieval interpreters of Aristotle. Anybody who wants to understand how the fusion of biblical Christianity and Greek philosophy have left a permanent imprint on western culture, history and knowledge can benefit from understanding his ideas.
Modern universities are still organised according to an Aristotelian model that was shaped by Aquinas and his contemporaries. The rise of western rationalism can be traced back to the medieval endeavour to universalise knowledge through the university curriculum, and to synthesise theology and philosophy in order to discern a rational order within the universe. Some scholars trace the origins of modern science back to this quest to study and interpret nature according to rational laws of cause and effect. Eventually, science and philosophy would break free of confessional influences, but Aristotelian philosophy as interpreted by Islamic, Jewish and Christian thinkers created the conditions in which "modern science" became possible.
Modernity's faith in science and progress has brought benefits but also disasters. Confronted by a looming environmental catastrophe, looking back at the bloody trail of imperialism, war and genocide that modernity has left in its wake, we need to rethink the role of reason, science and technology in the shaping of society and human behaviour. Aquinas reminds us that wisdom is more than knowing how things work or how useful they are. It is about discerning meaning as well as facts, asking not only what we can do but also what we should do in order to bring about a world of human flourishing.
In its understanding of law and politics, medieval Aristotelianism has had an enduring influence. Aquinas's conviction that law must be orientated towards the common good, responsive to custom and culture, and informed by wise reflection on the laws of nature, offers a coherent and integrated understanding of justice, law and virtue. Some thinkers, such as Amartya Sen and Martha

Nussbaum, argue that Aristotelianism offers a better approach to human development than many modern economic and political models.
Aquinas was a radical thinker and he fell under suspicion by the church authorities because of his enthusiasm for the "pagan" Aristotle. His openness to new ideas, and the thoroughness with which he studied and reflected upon these, are an example of the humility, dedication and patience that true scholarship entails. Of course his world view was different from ours, and many of his scientific ideas were wrong. However, he is in some ways closer to the discoveries of modern science than enlightenment philosophy. His understanding of the animality of the human species and of the naturalism of reason are compatible with neuroscience and evolutionary biology, except when these make unfounded judgments about the existence of God from within the limited field of scientific empiricism. Quantum physics reopens questions about consciousness, form and matter that were central to Aquinas's cosmology.
There is also much to criticise. Some of Aquinas's views, such as that heretics should be put to death for the common good if they refuse to recant, are deeply problematic. However, unless you are an absolute pacifist, questions still arise as to when a human being might legitimately kill another human being, whether in self-defence or for reasons of justice. Aquinas's thinking on the death penalty no longer informs western law – except in some American states – but his just war theory remains as relevant today as it was in the 13th century.
Aquinas's work is free of the vicious misogyny that one finds in some medieval texts, but he had a problem with women and he used Aristotelian arguments as well as biblical texts to justify their exclusion from public life and leadership. If Aquinas and his contemporaries had not barred women from access to university education, how different western history and knowledge might have been. A critical feminist reading of Aquinas can help us to understand some of the lingering values and beliefs that still influence modern attitudes to women.
Finally, Aquinas belongs within a living tradition that has influenced countless lives and has left a deep imprint on western history. Visit a medieval cathedral. Take a trip to the National Gallery. Read Dante or Chaucer. Listen to a mass by one of the great composers. These experiences require some understanding of the beliefs that informed Aquinas's world. We might not share those beliefs, but if we are not willing even to attempt to understand them, can we really understand who we ourselves are in relation to the history and culture that have formed us?