It's been a while since I engaged on this level

To my surprise, I've found myself embroiled in a creationist-evolutionist argument on, of all things, a *birding* blog. Most of my life does not involve engaging people in these types of arguments; obviously, I have my own convictions, but I'm better at, and have more interest in, doing other work than in arguing philosophy. And others do this much better than I. But I just couldn't help it today. I encountered the "you who believe in science have just as much faith as those who believe in the God of Creation" argument and just couldn't resist.

This guy said:

Deb: evidence? objective reasoned evidence? Scientifically verifiable evidence? Evolution is Science!? It all comes down in the end to epistemology. It always does. How do we know what we know? What are our standards for evidence, and how do we assemble evidence into reasonable, working definitions of truth?

I would argue that there are some scientists, even evolutionary scientists, and an great abundance of “scientifically minded modern people” who believe in evolution on exactly the same grounds. They have no direct experience of evolution in action. They have not done a single experiment to verify the truth of the theory, nor do they know anyone who has...

I couldn't help it; I couldn't just let this one go. I had already written my 1250 words for my novel (I'm doing National Novel Writing Month...50,000 words in the 30 days of November) and it's not like the laundry wasn't waiting. But...

Of course, Stephen, you’re right, it all comes down to epistemology.

How DO we know what we know? (Remember, knowledge–THINKING something is true–is different from what people call FAITH. I don’t know what the epistemological mechanism of “faith” is, or how it is distinguished from “make believe,” but it certainly isn’t KNOWLEDGE. If it were, then you and others would simply call it “knowledge,” not faith.)

I will answer the question you are actually asking, then, here. Leaving aside questions of faith, how do we know what we know?

The answer is that the only way that human beings can know anything is by the evidence of our senses. Our senses give us the primary data that our minds test and organize. Everything we know all ultimately comes back to sense data, and to our cognitive processing–the noticing of similarities and differences to create abstract concepts–of that sense data. Is something true? We check the evidence of our senses, and we check to verify that others are having the same experience.

When I say to someone that a certain thing is TRUE, I can only pound my fist and declare that to be the case if I have the objective evidence to which I can refer the person…evidence to which they have access through their senses, and reasoning based on the evidence of their senses.

No reputable scientist says the following: “Well, I BELIEVE this is true, but I can’t demonstrate conclusive evidence that would satisfy YOU, Deb. You can’t replicate my experience. But believe it’s true anyway, Deb. And respect me for it.” No, to the contrary: Scientists who have become established as knowing what they’re talking about have generally gotten that reputation BECAUSE they welcome honest inquiry into the topic, and because they hold out their claims as independently verifiable. They welcome validation from others willing to test the conclusion, and they welcome information from others trying but failing to replicate their conclusions. And, if they are honest, they welcome evidence refuting their conclusions.

That is, the way to learn things that are true about the world is through honest investigation of the natural world: I employ my mind to process the evidence of my senses. I trust scientists who employ the proper scientific method for the same reason, because they are engaged in an objectively verifiable quest for the truth. I do not trust the claims of people who do not welcome independent investigation, who do not hold their claims up to scrutiny.

This is why it is different to have provisional trust for a scientist’s claim than to trust religionists. The scientist always seeks to refine his understanding of the natural world *by examining the facts*, and testing, testing, testing. Religionists may be questioning, but faith (which seems to be commonly defined as “holding something to be true in the absence of verifiable fact”) precludes testing, indeed, precludes the very idea of proof.

If I encounter contrary evidence to something I think is true, then, I investigate further. And what do I investigate? The facts. How do I encounter facts? By seeing, hearing, smelling, touching, or tasting them. What else are facts? Abstractions that are generated as a result of cognitive processing of things that are experienced with the senses.

Emotions are facts, too, in the sense that it is a fact that unthinking people irritate me. But facts do NOT come into being by humans imagining them, or wishing for them, or feeling them. My irritation at someone is not *evidence* that they’re wrong. (If someone said to me: “How do you know we’re not all molecules in the spit of a giant dragon, Deb?” I can’t say to them: “Because the idea irritates me.”) Similarly, Stephen’s deep desire for there to be a Spirit in the Sky with a Plan is not evidence that one exists. Nor does the conviction of millions of people that something is true constitute evidence. Ask Gallileo.

I'm pretty sure he won't say, "Oh, wow, Deb, I get it now, thanks so much, thank heavens you've set me straight." But I still had to do it.