Science is About Discovering the Truth

As someone who works in IT, I hear and read a lot of comments about science. One common but unfortunate claim is that “science is not about finding truth.” While I won’t get into the underlying philosophical reasons behind this claim, I do want to at least respond to it on its face.

Etymology of the word “science”

The word science comes from the Latin scientia, meaning knowledge.

Plato said that knowledge is “justified true belief.” I’m not a big fan of Plato, but this is a good definition. Put another way, knowledge is what you believe to be true (a) that actually is true and (b) for which you have reason to believe is true. That’s less concise, but it hits all the important points.

If that’s not convincing, we could just skip to Encyclopedia Britannica, which says:

In general, a science involves a pursuit of knowledge covering general truths or the operations of fundamental laws.^[1]

What’s the point of science?

As practical matter, if science isn’t about finding truth, then why should anyone care about it at all? If the purpose of science isn’t to discover truth, then it’s nothing more than fictional storytelling.

Science should be about finding truth. The concept of truth us, at its core, a fundamental component of logic. The proposition that 2 +2 = 4 is either true or false. Some have said that science deals with facts and not truth, but this is a distinction without a difference. Science has to make decisions about facts and come to conclusions based on them. Saying that science deals with facts and not truth is like saying math deals with numbers but not equations. It’s, well, false.

The imprecise language of “science communicators” doesn’t help

Although scientists carefully think about their craft, many “science lovers” and “science communicators” do not. They throw around words like “facts” in completely wrong ways. One of the more common cliches is, “gravity is a fact.” Gravity is a force. It’s no more a “fact” than electromagnetism. A fact would be a measurement of gravitational energy. This might sound nit-picky, but when you’re dealing with science, nit-pickiness is important. You can’t just fudge definitions and assume everyone understands what you mean. But this is exactly what happens in popular science.

It’s probably science?

There’s been a shift towards saying that science deals not with certainty but only with probabilities. The insinuation is that the probability of a scientific claim is never 100%. Hence, you’ll see a scientific claim couched with a “probably” and usually with the disclaimer that it’s “the best explanation”. Take for example this bit from the National Institutes of Health:

Depression, like other mental illnesses, is probably caused by a combination of biological, environmental, and social factors, but the exact causes are not yet known.^[2]

You’ll likely never see a research paper that claims depression is certainly, without a doubt caused by a combination of those factors. The only assurance you get is that it’s probably the best explanation.

But now you have another problem: What’s the probability that is really is the best explanation? Perhaps some obscure researcher has a better explanation and hasn’t published it yet. The notion of “a best explanation” isn’t possible when you are only allowed to deal in probabilities. The “best explanation” then becomes “probably the best explanation.” So the whole thing falls apart.

Earth is certainly, and not probably, a sphere

Let’s take a more concrete example. There’s a 100% probability that Earth is a sphere. It’s not 99.9% or 99.0% or anything less. In fact, we can just forget probabilities altogether. It’s a scientific certainty that Earth is round. But as soon as you adopt the belief that science deals only in probabilities, you can no longer claim with 100% certainty that it’s a sphere. Instead, you’d have to say, “It’s probably a sphere” or “Earth being a sphere is the best explanation for why it looks round.” That’s ridiculous!

Knowledge is necessarily certain

Science means knowledge, and knowledge is necessarily certain. If you think you know something but aren’t certain, then you don’t truly know it.

Part of the solution then to the watering down of the word “science” is to avoid misusing it. That means, to the chagrin of many, removing the moniker of “science” from disciplines that don’t always deal in certainties, i.e. knowledge. That means psychology, anthropology, and history aren’t science, just to name a few. That doesn’t mean they’re less valuable or less worthy of study, it just means they don’t meet the strict criteria of science.