What Makes Science Scientific?
This is a question that never got much play during my education. I just learned scientific facts and theories out of my textbooks, ran simple experiments, and wrote up reports on my findings. As a result, science was never very inspiring to me. What did I know about how scientists came up with these facts, tested their hypotheses, and justified the theoretical basis for this knowledge? I've always valued the scientific method, but never questioned its epistemological foundation.
Turns out this question is very interesting philosophically and essential to avoiding sloppy thinking and erroneous judgments. Especially today, what with the constant assault on reason and science from right-wing media outlets and faith-based pseudo-scientific foundations, it appears that this topic is critical to preserving and building on what scientific progress we have made. Perhaps, every high-school and college student should be required to take a philosophy of science course that teaches critical thinking skills, if only to combat the ubiquitous ideological and rhetorical attacks on science. Otherwise, we're leaving them to watch reruns of Carl Sagan's Contact on TNT in the hope that Jodie Foster's querulous questioning of faith and championing of science sparks a discussion of how important it is to have a rational framework for understanding the mysteries in our world.
It wasn't until I read a philosophy textbook on critical thinking called, How to Think About Weird Things by Theodore Schick and Lewis Vaughn that I began to think about the framework that helps us better understand our world and how it works. Scientific method relies on careful observation and the creation and testing of hypotheses. But how can we be certain that a hypothesis avoids error and represents the best understanding of the phenomenon we are trying to explain?
As Schick and Vaughn state in Chapter 7, "Science and Its Pretenders," we rely on the "criteria of adequacy":
"Because there is always more than one hypothesis to account for any set of facts and because no set of facts can conclusively confirm or confute any hypothesis, we must appeal to something besides the facts in order to decide which hypothesis is the most reasonable. What we appeal to are criteria of adequacy. These criteria help us determine how well a hypothesis accomplishes the goal of increasing our understanding." (Second ed., pg. 160)So, what are these criteria that help hypotheses produce understanding by systematizing and unifying our knowledge? In a nutshell:
- Testability: "A hypothesis is scientific only if it is testable, that is, only if it predicts something other than what it was introduced to explain." Note also: "To be testable, a hypothesis must make a prediction that goes beyond its background theory." (161)
- Fruitfulness: "Other things being equal, the best hypothesis is the one that is the most fruitful, that is, makes the most novel predictions." (164)
- Scope: "Other things being equal, the best hypothesis is the one that has the greatest scope, that is, that explains and predicts the most diverse phenomena." (167)
- Simplicity: "Other things being equal, the best hypothesis is the simplest one, that is, the one that makes the fewest assumptions." (169)
- Conservatism: "Other things being equal, the best hypothesis is the one that is the most conservative, that is, the one that fits best with established beliefs." (170)
So, how do we go about making a sound scientific inquiry into claims both reasonable and irrational? Schick and Vaughn suggest a four-step SEARCH formula:
- State the claim.
"It's vital to state the claim in terms that are as clear and as specific as possible." (236)
- Examine the evidence for the claim.
What are the reasons, either in the form of empirical evidence or logical arguments, for accepting the claim? To do this effectively, you must:
- Determine the exact nature and limitations of the empirical evidence. (Any reasonable doubts about the data or research?)
- Discover if any of these reasons deserve to be disqualified. (Does support for the claim break down because of wishful thinking, faith, unfounded intuition, or subjective certainty?)
- Decide whether the hypothesis in question actually explains the evidence. "...a good hypothesis must be relevant to the evidence it's intended to explain." (236-37)
- Consider alternative hypotheses.
This step involves creativity and openness of mind so that you can counteract the built-in bias toward a favorite hypothesis, consider other possibilities, and change your view in light of good reasons. (238)
- Rate, according to the criteria of adequacy, each hypothesis.
- Testability: "Can the hypothesis be tested? Is there any possible way to determine whether the hypothesis is true or false?" (238)
- Fruitfulness: "Does the hypothesis yield observable, surprising predictions that explain new phenomena?" (238)
- Scope. "How many different phenomena can the hypothesis explain?" (239)
- Simplicity. "Is this hypothesis the simplest explanation for the phenomenon?" (where simplest means makes the fewest assumptions) (239)
- Conservatism. "Is the hypothesis consistent with our well-founded beliefs? That is, is it consistent with the empirical evidence--with results from trustworthy observations and scientific tests, with natural laws, or with well-established theory?" (239)