Worldviews

An Introduction to the History and Philosophy of Science

Richard DeWitt

• Publisher: Wiley-Blackwell
• Year: 2018
• ISBN:
  9781119118992
• Edition: 3
• Topic: Philosophy
• Subtopic: Philosophy & Ethics in Science

Winner of the 2018 Choice Award for Outstanding Academic Title! PRAISE FOR PREVIOUS EDITIONS

"This is a brilliantly clear introduction (and indeed reframing) of the history and philosophy of science in terms of worldviews and their elements…. In addition, the book is incredibly well-informed from both a scientific and philosophical angle. Highly recommended."
Scientific and Medical Network

"Unlike many other introductions to philosophy of science, DeWitt's book is at once historically informative and philosophically thorough and rigorous. Chapter notes, suggested readings, and references enhance its value."
Choice

"Written in clear and comprehensible prose and supplemented by effective diagrams and examples, Worldviews is an ideal text for anyone new to the history and philosophy of science. As the reader will come to find out, DeWitt is a gifted writer with the unique ability to break down complex and technical concepts into digestible parts, making Worldviews a welcoming and not overwhelming book for the introductory reader."
History and Philosophy of the Life Sciences, vol. 28(2)

Now in its third edition, Worldviews: An Introduction to the History and Philosophy of Science strengthens its reputation as the most accessible and teachable introduction to the history and philosophy of science on the market. Geared toward engaging undergraduates and those approaching the history and philosophy of science for the first time, this intellectually-provocative volume takes advantage of its author's extensive teaching experience, parsing complex ideas using straightforward and sensible examples drawn from the physical sciences.

Building on the foundations which earned the book its critical acclaim, author Richard DeWitt considers fundamental issues in the philosophy of science through the historical worldviews that influenced them, charting the evolution of Western science through the rise and fall of dominant systems of thought. Chapters have been updated to include discussion of recent findings in quantum theory, general relativity, and evolutionary theory, and two new chapters exclusive to the third edition enrich its engagement with radical developments in contemporary science.

At a time in modern history when the nature of truth, fact, and reality seem increasingly controversial, the third edition of Worldviews presents complex concepts with clarity and verve, and prepares inquisitive minds to engage critically with some of the most exciting questions in the philosophy of science.

Part I
Fundamental Issues

In Part I, we explore some preliminary and basic issues involved in the history and philosophy of science. In particular, we will discuss the notion of worldviews, truth, evidence, empirical facts versus philosophical/conceptual facts, common types of reasoning, falsifiability, and instrumentalism and realism. These topics provide the necessary background for our exploration, in Part II, of the transition from the Aristotelian worldview to the Newtonian worldview, and also for our exploration, in Part III, of recent developments that challenge our own view of the world.

1
Worldviews

The main goal of this chapter is to introduce the notion of a worldview. As with most of the topics we will explore in this book, the notion of a worldview turns out to be substantially more complex than it at first appears. We will begin, though, with a relatively straightforward characterization of this notion. Then as the book progresses, and we come to appreciate more about the Aristotelian worldview and about our own worldview, we will come to a better appreciation of some of the complexities involved.

Although the term “worldview” has been used fairly widely for over 100 years, it is not a term that carries a standard definition. So it is worth taking a moment to clarify how I will be using the term. In the shortest of descriptions, I will use “worldview” to refer to a system of beliefs that are interconnected in something like the way the pieces of a jigsaw puzzle are interconnected. That is, a worldview is not merely a collection of separate, independent, unrelated beliefs, but is instead an intertwined, interrelated, interconnected system of beliefs.

Often, the best way to understand a new concept is by way of an example. With this in mind, let's begin with a look at the Aristotelian worldview.

Aristotle's Beliefs and the Aristotelian Worldview

In the western world, what I am calling the Aristotelian worldview was the dominant system of beliefs from about 300 BCE to about 1600 CE. This worldview was based on a set of beliefs articulated most clearly and thoroughly by Aristotle (384–322 BCE). It is worth noting that the term “Aristotelian worldview” refers not so much to the collection of beliefs held specifically by Aristotle himself, but rather to a set of beliefs shared by a large segment of western culture after his death and that were, as noted, largely based on the beliefs of Aristotle.

To understand the Aristotelian worldview, it will be easier to begin with Aristotle's own beliefs. Following this, we will discuss some of the ways these beliefs evolved in the centuries after the death of Aristotle.

Aristotle's Beliefs

Aristotle held a large number of beliefs that are radically different from the beliefs we hold. Here are a few examples:

1. The Earth is located at the center of the universe.
2. The Earth is stationary, that is, it neither orbits any other body such as the sun, nor spins on its axis.
3. The moon, the planets, and the sun revolve around the Earth, completing a revolution about every 24 hours.
4. In the sublunar region, that is, the region between the Earth and the moon (including the Earth itself) there are four basic elements, these being earth, water, air, and fire.
5. Objects in the superlunar region, that is, the region beyond the moon including the moon, sun, planets, and stars, are composed of a fifth basic element, ether.
6. Each of the basic elements has an essential nature, and this essential nature is the reason why the element behaves as it does.
7. The essential nature of each of the basic elements is reflected in the way that element tends to move.
8. The element earth has a natural tendency to move toward the center of the universe. (That's why rocks fall straight down, since the center of the Earth is the center of the universe.)
9. The element water also has a natural tendency to move toward the center of the universe, but its tendency is not as strong as that of the earth element. (That's why, when dirt and water are mixed, both tend to move downward, but the water will eventually end up above the dirt.)
10. The element air naturally moves toward a region that is above earth and water, but below fire. (That's why air, when blown into water, bubbles up through the water.)
11. The element fire has a natural tendency to move away from the center of the universe. (That's why fire burns upward, through air.)
12. The element ether, which composes objects such as the planets and stars, has a natural tendency toward perfectly circular movement. (That's why the planets and stars continuously move in circles about the Earth, that is, about the center of the universe.)
13. In the sublunar region, an object in motion will naturally tend to come to a halt, either because the elements composing it have reached their natural place in the universe, or far more often because something (for example, the surface of the Earth) prevents them from continuing toward their natural place.
14. An object that is stationary will remain stationary, unless there is some source of motion (either self-motion, as when an object moves toward its natural place in the universe, or an external source of motion, as when I push my pen across my desk).

The beliefs just mentioned are only a small, small handful of Aristotle's views. He also had extensive views on ethics, politics, biology, psychology, the proper method for conducting scientific investigations, and so on. Like most of us, Aristotle held thousands of beliefs. But most of his beliefs were quite different from ours.

Importantly, Aristotle's beliefs were anything but a random collection of beliefs. When I say that the beliefs were not random, part of what I mean is that he had good reason to believe most of them, and the beliefs were far from naive. Every single one of the beliefs listed above turned out to be wrong, but given the data available at the time, every one of those beliefs was quite justified. To take just one example, the best scientific data of Aristotle's time strongly indicated that the Earth was at the center of the universe. The belief turned out to be wrong, but naive it was not.

By saying the beliefs were not random, I also mean that they form an interrelated, interlocking system of beliefs. To illustrate the ways in which Aristotle's beliefs were interrelated and interlocking, consider a wrong way and a right way of picturing them.

First, the wrong picture, which I will illustrate by an analogy with grocery lists. When most of us make grocery lists, we end up with a haphazard collection of items related only by the fact that we can, we hope, find them when we get to the grocery store. We could organize our grocery lists – with the dairy items in this part of the list, the bakery items in that part, and so on – but most of us simply do not bother. And the result, as mentioned, is a haphazard list with no particular relation between the items on it.

When you think of Aristotle's beliefs, do not think of them as like a grocery list of unrelated items. That is, do not picture the collection of beliefs as like the somewhat haphazard list in Figure 1.1. Instead, here is a better picture. Think of the collection of beliefs as like a jigsaw puzzle. Each piece of the puzzle is a particular belief, with the pieces fitting together in a coherent, consistent, interrelated, interlocking fashion, as the pieces of a jigsaw puzzle fit together. That is, picture Aristotle's system of beliefs more as it appears in Figure 1.2.

Figure 1.1 A “grocery list” of Aristotle's beliefs.

Figure 1.2 Aristotle's “jigsaw puzzle” of beliefs.

The jigsaw puzzle metaphor illustrates the key features of the way I am using the notion of a worldview. First, pieces of a jigsaw puzzle are not independent and isolated; rather, puzzle pieces are interconnected. Each piece of a puzzle fits with the piece next to it, and that piece fits with the pieces next to it, and so on. All the pieces are interconnected and interrelated, and the overall result is a system in which the individual pieces fit together into an interlocking, interconnected, coherent, and consistent whole.

Likewise, Aristotle's beliefs fit together, forming an interlocking, consistent system. Each belief is closely tied with the beliefs around it, and those beliefs in turn are closely tied to their surrounding beliefs, and so on.

To take just one example of how Aristotle's beliefs fit together, consider the belief that the Earth is the center of the universe. This belief is closely interconnected with the belief that the element earth has a natural tendency to move toward the center of the universe. After all, the Earth itself is composed primarily of the earthy element, so the belief that the earthy element naturally goes toward the center of the universe, and the belief that the Earth itself is at the center of the universe, fit together nicely. Likewise, both of these beliefs are closely tied to the belief that an object will only move if there is a source of motion. Just as my pen will remain stationary unless something moves it, so too with the Earth. Having long ago moved to the center of the universe, or as close to the center as they could, the heavy elements comprising the Earth will now remain stationary, because there is nothing powerful enough to move an object as massive as the Earth. All of these beliefs are, in turn, closely connected to the belief that the basic elements have essential natures, and the belief that objects behave as they do largely because of their natures. Again, the general point is that Aristotle's beliefs are interconnected like the pieces of a jigsaw puzzle are interconnected.

In addition, notice that in a jigsaw puzzle there are differences between the core pieces of the puzzle and the peripheral pieces. Because of the interconnections, a central, core piece cannot be replaced with a different-shaped piece without replacing almost the entire puzzle. A piece near the periphery, however, can be replaced with relatively little alteration in the rest of the puzzle.

In a similar vein, among Aristotle's beliefs we can distinguish between core and peripheral beliefs. Peripheral beliefs can be replaced without much alteration in the overall worldview. For example, Aristotle believed there were five planets (not counting the sun, moon, and Earth). Five planets are all that can be distinguished without the technology of recent years. But had there arisen evidence, say, of a sixth planet, Aristotle could easily have accommodated this new belief without much alteration in his overall system of beliefs. This ability of a belief to change without substantially altering the overall system of beliefs is typical of a peripheral belief.

In contrast, consider the belief that the Earth was stationary and at the center of the universe. In Aristotle's system of beliefs, this is a core belief. Importantly, this is a core belief not because of the depth of conviction Aristotle had in it, but rather because, like a puzzle piece near the center, it cannot be removed and replaced without dramatically altering the beliefs to which it is connected, which in turn would require altering almost his entire system of beliefs.

To illustrate this, suppose Aristotle tried to take his belief that the Earth was the center of the universe and replace it with, say, the belief that the sun was the center. Could Aristotle simply remove this belief, this piece of the puzzle, and replace it with a new belief that the sun is the center, and do so while still keeping most of the rest of the jigsaw puzzle intact?

The answer is no, because the new belief, that the sun is the center of the universe, would not fit into the rest of the jigsaw puzzle. For example, heavy objects clearly fall toward the center of the Earth. If the center of the Earth is not the center of the universe, then Aristotle's belief that heavy objects (those composed mainly of the heavy elements earth and water) have a natural tendency to move toward the center of the universe has to be replaced as well. This in turn requires replacing a multitude of other interconnected beliefs, such as the belief that objects have essential natures that cause them to behave as they do. In short...