In a recent video message for this year’s Science for Peace meeting, Pope Francis addressed one of the biggest problems with the way people tend to see science today. Namely, that one branch of science or scientific advance ‘will be seen as the only possible lens for viewing a particular aspect of life, society and the world’. In other words, some branches of science see themselves as ‘self-sufficient’ instead of recognising their need to be complemented by other forms of knowledge.

This feeling of self-sufficiency is one of the root causes of what’s called scientism: the viewing of the whole world through just one scientific lens. And there’s one science especially that the rest of them have deemed free to ignore and even chide as irrelevant: the science of theology.

We don’t often think of theology as a "science", but that’s exactly what it used to be. It was referred to as the "queen of the sciences", because the word scientia simply meant knowledge and the highest knowledge someone could arrive at was knowledge of God. We talk about science as a single thing or a single endeavor, but that’s not the proper way to think about it. There are, rather, many branches of knowledge that grow together and reveal different aspects of reality. What we refer to as science today would simply have been referred to as the natural, or empirical sciences back in the day since they dealt with the makeup of the physical world. The idea that the natural sciences are all that science is would have been nonsensical.

How do we begin to heal this breakdown in the sciences, then? How do we draw out the relationship between them that people don’t see? How do we allow for a fuller understanding of reality instead of a merely fragmented one?

Here, perhaps St Bonaventure could be of some help to us.

A Medieval Bigwig

When it comes to medieval philosophy, Thomas Aquinas was not the only game in town. There was also a highly respected bigwig by the name of Bonaventure, who was the Minister General of the Franciscans in the mid-thirteenth century. He was appointed a cardinal by Pope Gregory X and taught at the highly prestigious University of Paris for many years.

His most popular text is The Journey of the Mind to God, and it is a meditation on the ascent of the soul into union with God. The unique thing about this text is that it is not only a mystical text but it’s also a profoundly philosophical and theological one as well. None of these things are separable for Bonaventure. He wove them together to create some of the most powerful writing of the Middle Ages. Reading thinkers such as Bonaventure, for whom none of the sciences were ‘self-sufficient’ but actually relied on one another, is important for feeling out the web of connections between things.

For Bonaventure, what today we would call ‘science’ he called the first power of sight that we have (The Journey of the Mind to God, 1.11). It’s the ability to consider what things are, see their makeup, their weight, their shape, their species, how they work and what makes them tick. This is the most basic thing we do as humans, in some sense. Moreover, as we consider things in their breadth and variety and interrogate their origin and cause and purpose, we are able to trace the wisdom of God because creation reflects God like a mirror. Since God is the beginning and end of creation as a whole, to investigate and understand his creation is to do nothing other than begin to know God himself.

So far so good. But there’s something else here we need to follow – a turn inward that can help build the connection between the natural sciences and theology.

We perceive the created world through our five senses. But we only understand the created world, Bonaventure argues, through our interior sense of the mind and its reasoning (2.6). It is this interiority of the human person – this sense of something inner and immaterial (the mind) – that ‘glitters’ with the Divine Image. It is also this inner sense that the entire modern scientific enterprise is built upon.

We cannot go out and investigate the world or dissect things or experiment unless we assume that we have the basic ability to understand what’s out there; that ability to discern things and come to know them. The funny thing about this mind of ours is that it’s immaterial; which is also to say, it’s a spiritual reality. The mystery of human consciousness is a mystery for scientists precisely because it’s not clear how things like memory, imagination and intelligence come from chemical things happening in the brain. The obvious answer to this, for people like Bonaventure, is that they can’t. The mind is spiritual and it is one way in which we reflect and participate in who God is.

With this turn inward, Bonaventure is a lot like Augustine, who famously said, ‘You are nearer to me than my inmost being’. We can find traces of God in the universe, yes, but we won’t encounter the intimacy of God unless we begin contemplating the wonder of who we are. Unless we’re able to admit that there are simply some things about us that are not only improbable but impossible without the breath of life God gave us. Consciousness is one of them.

The Mystery of Love

Finally, in Bonaventure’s Journey of the Mind to God we encounter the importance of love and delight. The whole text is designed to communicate the importance of falling in love with the crucified Christ, of kindling a burning desire to love him. Because love, as always in the Christian tradition, is of supreme importance. Understanding without love is worth nothing (Prologue: 4; 1 Corinthians 13:2).

Which is why Bonaventure actually begins his discussion of the mind with a discussion of delight. Before we properly understand things, we take delight in them, wonder at them, enjoy them. We find ourselves mesmerised by their beauty (2.5). Every scientist does what he or she does because of this initial sense of wonder and delight in what they have seen. This experience is what comes first and it is an important aspect of what it means to love.

And in encountering the mystery of human love, we encounter the mystery of God.

The Catholic Church celebrates the feast of St Bonaventure on 15 July.