"On the Shoulders of Giants"

A 1675 letter by Isaac Newton has the line: "if I have seen further [than others], it is by standing on the shoulders of giants." This has become a saying for doing work that builds on earlier (and more fundamental) work. It was not the first time that metaphor was seen in print.

John of Salisbury in 1159 wrote:

Bernard of Chartres used to compare us to dwarfs perched on the shoulders of giants. He pointed out that we see more and farther than our predecessors, not because we have keener vision or greater height, but because we are lifted up and borne aloft on their gigantic stature.

This was in his work called Metalogicon. The Metalogicon was about the value of the Trivium (Grammar, Rhetoric, Logic). It consists of four sections that defend the Trivium against those felt that Grammar and Rhetoric were not important to the study of Logic. John would not have known Bernard, who died in the 1120s (John was a child then, going to grammar school in England). He did, however, study Rhetoric and Logic at Chartres under one of Bernard's disciples, Richard l'Evêque.

Although John attributes this to Bernard of Chartres, while John was at Chartres he also studied under William of Conches. John should have been unaware that William, in his 1123 commentary on the Institutiones grammaticae of Priscian, wrote:

The ancients had only the books which they themselves wrote, but we have all their books and moreover all those which have been written from the beginning until our time.… Hence we are like a dwarf perched on the shoulders of a giant. The former sees further than the giant, not because of his own stature, but because of the stature of his bearer. Similarly, we see more than the ancients, because our writings, modest as they are, are added to their great works.

John of Salisbury referred to himself as Johannes Parvus, "John the Little"; parvus can mean "little" or "small." he does not indicate in his writings that he was physically sort. Perhaps this was a humble moment in which he claimed to be not a giant.

A commentator on the Talmud, the Jewish Isaiah di Trans (c.1180 - c.1250) wrote:

For I heard the following from the philosophers, The wisest of the philosophers was asked: "We admit that our predecessors were wiser than we. At the same time we criticize their comments, often rejecting them and claiming that the truth rests with us. How is this possible?" The wise philosopher responded: "Who sees further a dwarf or a giant? Surely a giant for his eyes are situated at a higher level than those of the dwarf. But if the dwarf is placed on the shoulders of the giant who sees further? ... So too we are dwarfs astride the shoulders of giants.

Anyway, the phrase caught on long before Isaac Newton wrote his letter to Robert Hooke. But back to John of Salisbury. Besides defending the Trivium and the verbal arts, he had some strong opinions about things that could be proven, and some strong arguments about the medical profession of his day. I'll talk about those tomorrow.

John of Salisbury

I mentioned yesterday that John of Salisbury was one of the medieval authors who understood eclipses. He had a long career that I'll get out of the way before we look at his extensive writings.

John of Salisbury (c.1110 - 1180) was an Anglo-Saxon author and philosopher in Norman England, and so his family was not going to be particularly prominent. His writings show us that he went to a parish school as a boy. About 1136 he went to France where, like Arnold of Brescia,  he studied under Peter Abelard. He wrote about students and teachers there, giving us a view into one of the oldest universities. John also studied at Chartres under William of Conches.

About 1140 he was back in Paris, studying theology and supporting himself by tutoring the sons of nobles, sharing an apartment with Peter of Celle, who became a Benedictine and abbot of St. Rémy at Reims. While attending the Council of Reims in 1148, it is believed he was introduced by Bernard of Clairvaux to Theobald of Bec, the Archbishop of Canterbury. John became Theobald's secretary.

This position brought him back to England, where he was secretary to Theobald for seven years and where he came to know Thomas Becket. John also made trips to Rome during this time, where he got to know Nicholas Breakspear, the only Englishman to become pope (as Adrian IV).

In 1176, John was made Bishop of Chartres, a position he held until his death on 25 October 1180. His successor as bishop was his longtime friend and former roommate in college, Peter of Celle.

Now that we have some background on the man, we'll turn next to his written works.

Natural Philosophy

William of Conches (1085-1154), as mentioned yesterday, wrote on Plato's Timaeus. The Timaeus was a popular work or analysis because, for a long time in the Middle Ages, it was the only work of Plato accessible to scholars. Medieval scholars, looking to create a "unified theory" of the world, did not want to reject material from the venerated philosophers of the past—even if they were pagan. Instead, they tried to reconcile earlier writers to Christianity to make a complete picture.

Natural Philosophy—the attempt to explain how the world works—had its own goal of reconciliation: to explain how a world where choice was possible could co-exist with a God who oversaw and was the motivator of everything that happened. There is an idea that science and religion find themselves in conflict because determining physical causes is pointless in a world where God determines everything. The classic example of this is: what should a good Christian do if he becomes ill? Should he visit a priest or a doctor? Is illness a divine punishment for sin, or best understood as a physical failing that can be treated?

In the Middle Ages, of course, the sufferer would not take chances, and would visit both. But men like William of Conches wanted to bring these two sides intellectually into agreement. He recognized that God was the ultimate cause: His omnipotence made him the primary cause that underlies everything in the universe. As a natural philosopher, however, William drew a distinction between this aspect of God and His methods for achieving His aims. There are actions, he said, that are secondary causes.

For instance, if I put a kettle with water on the stove to make tea and turn on the flame, my actions will cause the water to boil. A natural philosopher can examine the boiling water, measure its temperature, gauge the length of time it takes to boil and how active the boiling is, and find uses for boiling water. Those are all secondary causes and effects, however; the primary cause is my desire to make tea and my application of heat. The natural philosopher can learn about heat and water without knowing about my desire for tea. If he observes the water heating several times, he will learn to predict the outcome through his understanding of natural law.

What about miracles? Well, a miracle is an event that we recognize happens that contravenes natural law; in order to recognize a miracle, however, William said we first need to thoroughly understand natural law. By analyzing natural laws, the philosopher does not challenge God's authority; he is analyzing the secondary causes, with the understanding that they are an "additional layer" between God and the world.

Given that miracles are possible, however, does this invalidate our observations of natural law and are reliance on our predictive ability regarding them? For his part, William was very clear: he believed that God was loving and consistent, rather than capricious. The natural laws that God established would remain natural laws forever. The few times we observe something different are either a miracle—an anomaly that we do not have to understand, or merely more information that will enhance our understanding of natural law.

The Flat Earth

In 1620, Sir Francis Bacon published Novum Organum ("The New Organon," by which he meant a new interpretation of nature). In it, he claimed that the ancient fathers of the Christian church did not tolerate a belief in a round Earth. It is probably this work that influenced the popular belief ever since that the Middle Ages, or religion, were steadfast in their belief in a flat Earth.

There is plenty of evidence to the contrary, however. True, there was "evidence" in the Middle Ages of a flat Earth. The Mappa Mundi (Map of the World), meant to portray the part of the world believed to be habitable, does make the world look flat and finite. Way back in he 3rd century BCE, however, Eratosthenes had coined the term "geography" and measured the circumference of the clearly round Earth by noting the difference in shadows of a stick at noon on two points many miles apart; the angles and length of the shadows told him that the sun was shining down on the surface at different angles, and the surface was therefore curved.

As revered an early christian as Boethius (480-524, mentioned here) in De consolatione philosophiæ (The Consolation of Philosophy) reminds us of how small we are in the grand scheme of things with this:

It is well known and you have seen it demonstrated by astronomers, that beside the extent of the heavens, the circumference of the earth has the size of a point; that is to say, compared to the magnitude of the celestial sphere, it may be thought of as having no extent at all.

Medieval sources even quote Pliny the Elder's figure of 29,000 miles for the circumference, a remarkably accurate figure.*

So was there a conflict between science and Christianity? Depends who you talk to, I suppose. William of Conches (1085-1154), who may have been a tutor to the young man who became King Henry II of England, wrote extensively on reconciling the origin of the cosmos in Plato's Timaeus with Genesis. The Bible may have described the earth as flat, but William knew this should not be taken literally, explaining:

The authors of Truth are silent on matters of natural philosophy, not because these matters are against the faith, but because they have little to do with the upholding of such faith, which is what those authors were concerned with.

As learning spread—specially with the advent of mass printing—perceptions of the Earth's shape would have spread thanks to re-printed classical works. Columbus' idea to go west to arrive at an eastward point was not a risky gamble or a brilliant insight. Other "facts" in the Bible were also understood to be not literal: Pope Innocent III, for instance, knew that the Moon shone with reflected light, even though the Bible refers to the Sun and Moon as "two lights."

So what account for the learned Bacon's statement? It may have something to do with the conflict between Galileo and the Church. Although the famous trial would not take place until 1633, Galileo had received a formal Admonition in 1616, warning him:

to relinquish altogether the said opinion that the Sun is the center of the world and immovable and that the Earth moves; nor further to hold, teach, or defend it in any way whatsoever, verbally or in writing; otherwise proceedings would be taken against him by the Holy Office; which injunction the said Galileo acquiesced in and promised to obey.  [link]

It is very likely that Bacon and the rest of Europe's scientific community was aware of this growing conflict. In this historical context, Bacon's statement can be seen as a condemnation of the Church because of a recent action—even though for centuries the knowledge of a round Earth was common.

*In fact, the original figure might have been more accurate than we suspect: it was given in Greek stadia, a measurement which meant different things to different users. Our best interpretation is 29,000 miles, but if Pliny were using stadia of a slightly shorter length... .