Science and technology are powerful forces in our modern world. Innovations in transportation, communications, agriculture, and medicine have dramatically improved the quality of human life. On the other hand, science and technology have also made it possible to destroy life on an unprecedented scale through instruments of modern warfare. It’s no wonder then that science evokes a wide range of emotions—from praise and hope to fear and distrust. In addition to a wide array of applied technologies, science also has unique explanatory power: it has revealed the immense age of the universe, the history and development of life, and the delicate balance of our environment. Science inspires us and challenges us, and like it or not, it continues to shape our lifestyles and self-understanding.
Given the diverse attitudes towards science in our country, it is important that we ask the question, “What exactly is science?” Does it give us absolutely certain knowledge? Is science truly objective and value-free? Does it eliminate purpose from the universe? Are there any limits to science?
What is science? Many authors have labored over this question, but the Spanish physicist and philosopher Mariano Artigas has offered a particularly insightful three-pronged definition:1
1. Science is a goal-directed activity towards the knowledge and control of nature
As a goal-directed activity, science itself has purpose—it strives towards a more complete understanding of nature and the ability to modify it to serve human needs. These goals are understood to be valuable and worth the painstaking efforts necessary to achieve them. In these respects, science has values at its very core.
2. Science is a well-defined method
Another essential component of science is its method. Both Artigas and physicist Ian Hutchinson maintain that the scientific method defines science itself. Hutchinson singles out two particular characteristics that distinguish it from other forms of intellectual inquiry.2 First, science relies upon experimental or natural evidence. Ideally, this evidence should be reproducible and thus subject to verification by other researchers. (Note: in some fields such as astronomy where one cannot actually reproduce events that take place many light-years away, one can make numerous observations as a basis of comparison. In disciplines such as the life sciences, biologists can rely on a multiplicity of specimens to approximate the need for reproducibility.)
Second, besides requiring a particular kind of evidence, the scientific method also demands certain types of explanations. They should be mathematical, mechanical, measurable, or quantifiable in some way. For example, one can take measurements of mass, number, length, time, velocity, pressure, volume, or many other discrete units. The goal is to create unambiguous results that are capable of creating consensus among other researchers, and understandable by anyone else who carefully investigates the topic.
3. Science is a body of knowledge
In addition to being a goal-directed activity and a highly-specific method, science is also a body of knowledge. This knowledge is not just an assemblage of facts, but also theoretical constructs consisting of concepts, laws, and theories. Though scientific knowledge is constantly in flux, these discoveries and formulations are thought to reflect in some way the underlying reality of the universe.
With these three dimensions of science firmly in mind, we have the basis for distinguishing science from non-science.3
Philosophical Foundations of Science
Despite its day-to-day reliance on empirical and measurable data, science rests on certain assumptions about knowledge itself that cannot be empirically proven. These basic premises are what allow us to ask scientific questions in the first place. While the lack of complete certainty is perceived by critics as a weakness, the dynamic nature of science is actually a great strength4—since scientific presuppositions are not set in stone, new discoveries produce feedback that enables us to reassess, and if necessary, modify our assumptions.5 Furthermore, our understanding of natural phenomena can improve dramatically over time provided that we first accept that “understanding” is possible in principle. With that in mind, let’s investigate some of the implicit premises that undergird the scientific enterprise and speak to the knowability of the world.6
Setting aside various nuances, realism basically maintains that there is a world that exists outside our minds. While this may seem self-evident, it is exceeding difficult, if not impossible, to demonstrate. Everything that we have ever experienced is mediated through our minds, and while we can imagine that an external world is stimulating our senses, the fact remains that we are still thinking about it. Plato and Descartes have famously wondered whether our lives are just a continuous dream, and in our own culture, the movie Inception explored this very same question. In a related way, the movie The Matrix invited us to consider whether our “reality” was just a computer simulation designed to placate us.
Philosophers have debated this topic ad nauseum, but scientists, in order to do their work, must suppose that there actually is an external world—otherwise, they would only be chasing dreams and illusions. The challenge of science is to figure out what the universe contains and how it works, not whether it exists at all.
Nature exhibits order and regularities
Science relies on the premise that there is some underlying order the universe that we can discover and understand. If nature were to totally reshuffle every day, none of the experiments we conducted yesterday would be reliable today, and there would be little basis for making any judgments about past or future events. Therefore, scientists depend on some degree of regularity within the universe in order to carry out their goals—namely the search for consistent patterns, structure, and organization of the physical world.
At the same time, science does not have a particular commitment to exactly what kind of order exists. Thus this presupposition is actually a flexible, accommodating principle that adapts to ongoing empirical research. Lest we think that modern discoveries have marred our conception of an ordered universe, even chaos theory and Heisenberg’s uncertainty principle have given rise to a better understanding about how nature is organized.7
Another distinguishing characteristic of modern science is the premise that every event is caused by another event; things don’t simply happen for no reason at all.8 When investigating various aspects of the natural world, scientists search for natural causes and natural explanations of those phenomena.9 Though this approach may seem unnecessarily constrained, it has had great success in accounting for previously mysterious terrestrial events like lightning, earthquakes, and volcanic eruptions, as well as celestial phenomena like comets, eclipses, and supernovae. On the human level, scientific research led to the development of germ theory, which has led to effective treatments for numerous diseases that used to be deadly. These are compelling practical reasons to adopt a scientific approach to natural phenomena, rather than being resigned to fate or purely supernatural interpretations of our world.
Natural laws regulate the universe
If you accept the three basic premises that there is a world external to your senses, that nature exhibits consistent and unvarying order, and that causality is universal, it follows that one can formulate natural laws that effectively describe and predict many phenomena that we encounter. In fact, describing the behavior of matter through mathematics and statistics has been enormously successful at the small scale of physics and chemistry, and computational approaches hold great promise in many fields of biology. Natural laws also help explain events on the largest scales of astronomy and cosmology.
On the other hand, human activities continue to vex us. It is notoriously difficult to predict political developments, economic fluctuations, and social movements. Some people think that this is due to fundamental uncertainties and vicissitudes of human behavior. Others think that it is “just a matter of time” before scientists uncover the laws that dictate our individual and collective decisions.
Are naturals laws completely universal in time and space, absolutely certain and inviolable? Not necessarily—since empirical science only makes measurements at particular times and places, science itself cannot demonstrate that natural laws invariably apply to every event in the universe. Uncertainty is a central feature of the human condition, and not even science can eliminate it completely.
It should now be evident that science does not proceed from completely provable foundations. However, its fundamental principles are not arbitrary or dogmatic. The practice of science itself enables us to revisit and modify our initial premises. As Mariano Aritgas puts it, “Scientific progress provides feedback on its presuppositions—it retrojustifies, enriches, and refines them.” Science may not give us the complete certainty that many humans seek, but it does provide us with profound and remarkably reliable insights into the physical world we inhabit.
We have just examined how science is grounded in a number of philosophical premises without which empirical research cannot proceed. But given how often we hear that science is purely objective and impartial, it may be surprising to learn that science also contains ethical premises. In fact, certain human values are intrinsic to the entire scientific enterprise. Research communities collectively embrace intellectual freedom, the right of dissent, cooperation, accurate communication of results, and personal responsibility for one’s claims.10 When individual practitioners or institutions circumvent these values, great damage can occur not only to the progress of knowledge, but in certain fields like biomedicine, they can endanger human life.11
Science is not an activity carried out by uncaring automatons. It is a distinctly human endeavor conducted by those who believe that it is better to know than be deceived and that it is better to thrive than to suffer. Thus, to call science a strictly value-free and objective enterprise is a misnomer. Instead, it promotes distinct human values: the longing to understand the world that surrounds us, and the desire to improve and perpetuate human society.12, 13
Unifying scientific knowledge
The ability to connect and explain seemingly unrelated phenomena is a hallmark of modern science and one of the key ways by which we evaluate the strength of theories. For instance, up until the end of 16th century, European intellectuals considered the motion of the heavens to be utterly distinct from motion here on earth. Celestial objects such as planets and stars moved in circles and earthly objects moved in straight lines. This notion, which was inherited from the ancient Greeks, accorded well with our common sense. But visionaries such as Johannes Kepler, Galileo, and Isaac Newton proposed that there were a set of underlying physical laws that determined all the motion in the universe, regardless of where it took place. Though their claims seemed counter-intuitive, their laws of motion predicted observable phenomena much more accurately than ever before.
Other great scientific advancements also unified disparate areas of knowledge. In the 19th century, James Maxwell developed a theory with astonishing explanatory power, encompassing the fields of electricity, magnetism, and optics. Electricity was a complicated phenomenon exhibited by lightning strikes, static shocks, and a few strange fish. Seemingly unrelated was magnetism, evidenced by a certain kind of rock known as lodestone which attracted pieces of iron and had the uncanny ability to act as a directional device (a property familiar to anyone who has used a compass). The third field of exploration was optics, the branch of physics that studies the properties of light. Maxwell’s great achievement was to bring together all three of these fields through his electromagnetic theory of light.14
The effort to unify scientific knowledge continues unabated today. Physicists have been working towards unifying the four fundamental forces of nature: electromagnetism, the weak nuclear force, the strong nuclear force, and gravitation. In popular discourse this effort has been described as the “theory of everything.” Is this label merited? Will all knowledge eventually be unified by science?
Theoretical physicist Lisa Randall of Harvard University thinks the label “theory of everything” is a great misnomer. Even if physicists were able to unify all four of the basic forces, it would still not constitute a complete theory of everything. Knowledge of all the underlying properties of matter and energy would not be sufficient to fully understand all phenomena in the world. Instead, Randall thinks that we need explanations at a variety of scales, not just the most fundamental.15 That is why there are so many different scientific disciplines in existence today—and why they continue to multiply.
Though science has tremendous explanatory power and has expanded rapidly in the past several hundred years, it still has limits. In her book Knocking on Heaven’s Door, Professor Randall cautions us against thinking that our scientific knowledge is absolutely certain:
When scientists say we know something, we mean only that we have certain ideas and theories whose predictions have been well tested over a certain range of distances or energies. These ideas and theories are not necessarily the eternal laws for the ages or the most fundamental of physical laws.16
Though our understanding grows over time, we simply cannot measure every event in the universe at every moment. Scientific knowledge is reliable and well tested, but it is still contingent and subject to revision.
Another way science is limited is through its disciplinary boundaries. Institutions of higher learning are organized by academic departments, and these different departments are generally grouped into categories such as natural sciences, social sciences, and humanities. Though the boundaries are not completely airtight, they help each discipline to focus on questions that are appropriate for their specific methodology.
However, given the increasing role of interdisciplinary research and the rapid discoveries of science, some people believe that the methods of natural science should be extended to all phenomena, including those traditionally explored by the humanities and social sciences. Moreover, enthusiasts such as E.O. Wilson, author of the Pulitzer Prize-winning book On Human Nature, have suggested that natural science may eventually eclipse the humanities and social sciences altogether, making them superfluous.
Though it seems appealing to have a single, unified approach to all topics of investigation, this approach ignores the possibility that the very reason why natural science is so powerful is that it avoids certain topics and restricts itself to particular domains. Questions of philosophy, history, theology, and the arts are often not amenable to strict quantification and reproducible testing. By imposing its methodology on these other areas, natural science could impoverish our understanding of the world rather than enrich it. In particular, science may not be well-equipped to answer certain questions related to purpose.
A Purposeless Universe?
Physicist Steven Weinberg is famous for saying, “The more the universe seems comprehensible, the more it also seems pointless.” But the fact is, when conducting scientific research, Weinberg and his colleagues aren’t directly looking for purpose, they are investigating what the universe is made of and how it works.18 This is the quest for structure and function, two areas in which science excels. Ultimate purpose, if there is any, may not be reducible to such knowledge alone.
On a smaller scale, we should not discount the fact that nearly all human activities, including science itself, are organized for specific purposes. But that raises the question, is there any purpose outside of human consciousness? Some scientists insist there is not. But are they justified in believing that in our incredibly vast cosmos, there is absolutely no other purpose than what we ourselves create? To take such a position implies a particular form of human uniqueness, a concept that many of these same scientists have usually been hesitant to embrace.
Indeed, the quest to discover the ultimate purpose of the cosmos presupposes that there is some non-human agent with an intention for that object. Thus, this issue is intimately connected with whether or not there is a self-conscious “mind of the universe”, as the ancient stoic Seneca described, or the “maker of heaven and earth” that we Christians have affirmed in our earliest creeds. However, if such an agent can’t be sufficiently described by mathematics and/or material causes, then this subject is actually not a suitable target for scientific inquiry.19 In looking for purpose, we are looking beyond the limits of science.
Though humanity has a long, complicated, and contentious history, one characteristic that unites all societies is their longing to understand the world and their place within in. This quest has taken many forms: religious expression, literature, philosophy, art and science, all of which continue to thrive in our modern world. Some authors and popular figures depict science as completely distinct from other modes of human inquiry, but the fact remains that modern science largely emerged from and was enriched by Christian intellectual traditions, particularly natural philosophy.20 This does not diminish the value of science by any means—to the contrary, by carefully examining the conceptual foundations of science, its goals and limits, we are better prepared to grasp its true potential.