A brief history of philosophy, part 4: Aquinas reconciles Christianity with Aristotle

Thomas Aquinas

Last week we saw how Augustine reconciled Plato with Christianity; but Aristotle, with his logic and his empiricism, was difficult to reconcile with a book that already claimed to have all the answers, and so that didn’t happen until 900 years later.

Most of Greek philosophy had been lost in the West because of the fall of Rome and the rise of an intolerant Christianity; but it had been preserved in the Arab world due to the conquest of previously Greek territory throughout Egypt and the Middle East. In the 12^th century, Averroes (Ibn Rushd), a Moor in Spain (by this time, Muslims had conquered the whole of the Middle East and North Africa, and were moving into India and Europe), brought the teachings of Aristotle back into Europe. Averroes had reconciled Aristotle with Islam (there is one truth, but two paths to it – philosophy and religion).

In Paris, Thomas Aquinas (1225-1274) discovered the writings of Averroes, and began to assimilate his work into Christianity too. Before Aquinas, it was thought that God formulated natural laws and we were not supposed to understand them. Things are only comprehensible through God. Aristotle argued that we can understand matter and natural laws as they are simply mechanical, but the essence of matter and nature – i.e. life and the soul – cannot be understood by humans, only by God. Aquinas reintroduced the Aristotlean idea that certain things can be understood by human reason and empiricism, but that the most important areas of existence can only be approached via faith.

In this way, Aquinas united faith and reason for Christians, which was vital for science to be allowed to exist at all. Faith was still compulsory, but in some areas, for the first time in 1000 years, people began to examine the natural world objectively. Studying ‘natural laws’ was allowed so that people could better understand the mind of God. Budding scientists were less worried about being branded as heretics (something that usually had extremely painful consequences; ‘Saint’ Thomas himself clearly said that heretics should be killed).

Ibn Rushd / Averroes

If civilisation was in decay in Augustine’s day, in Aquinas’s time, Europe was booming. There was population and economic growth, and trade with the East was growing. Studying worldy things in this era was much less scary than in Augustine’s time. Aquinas and the ‘Scholastics’ were dedicated to uniting faith and reason. They stressed several things, and the time was ripe to stress them:

1. God made the world and the human intellect, so they couldn’t be so bad. If humans use their intellect to discover more about the world, it would reveal more of God’s wonders and increase religious fervour, not dampen it.

2. Asking humans not to think was like asking birds not to fly. They wouldn’t be performing to their full capacity, and therefore not glorifying God as much as they could. We have to use the gifts that God gave us.

3. Humans are so far beneath God, that we’re not capable of understanding his ideal forms – we can only approach them, and try to understand them by observing material objects in the sensible world. We can know the particular, and through it, try to understand more about the general (here are the stirrings of the principle of induction).

Therefore, to try to understand more about God through observing and thinking about the material world was a religious requirement. He had reconciled Christianity and Aristotle, and made Greek rationality and empiricism Christian things to do. This was a massive change in direction, and obviously the scientific revolution couldn’t have happened without it. There must also have been a realisation that if the Islamic world had all this ancient knowledge and the Christian world didn’t, they were going to fall behind in the technological race for dominance.

Aquinas’s model of human knowledge had science at the bottom, philosophy above it and theology at the top; so empiricism and reason could be used to discover things at lower levels, but not at the higher level. Higher truths were only accessible through revelation – and so church leaders were content. Little did they know what a Pandora’s Box had been opened, and that by allowing reason a foothold, they had inadvertently sown the seeds of the church’s demise. Aquinas himself had no desire for science and philosophy to overshadow religion, but after his work in disinterring Aristotle, that was the way society was ultimately headed.

Next: the Roots of Renaissance.