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On Fall Foliage, Nathan Lents Comes Up Short

Tom Gilson

Editor’s note: Tom Gilson is a Senior Editor for The Stream and the author most recently of Too Good to Be False: How Jesus’ Incomparable Character Reveals His Reality. The exchange with Dr. Lents continues at Gilson’s blog, Thinking Christian, from which this is republished with permission.

He’s a writer, he’s a professor of biology, and Nathan Lents thinks my Evolution News essay on the gift of fall colors this week is “silly.” It’s “what passes for serious thought at the Discovery Institute,” and it’s pretty bad, he wants us to know. He stated as much in a series of tweets starting here, which he gave me permission to reproduce.

I’m afraid he’s not going to like my answer. I’m not going to re-visit my article’s thesis. As stated, I wrote it by dictation while walking through the woods. It’s obviously incomplete and intentionally not rigorous, and I think most readers would recognize its intent. Instead, I’m going to focus on what Lents has to say. He says my article doesn’t represent serious thought. Does his response? The evidence, unfortunately, says no. There are far too many errors in such a small amount of space, too many fallacies in such a short series of tweets.

Sarcasm Isn’t an Argument

Let’s take it a step at a time. (I’ve compiled his entire series of tweets into block quotes here.)

Another strange claim from #IntelligentDesign: the lovely colors of #autumn were purposely designed for humans to enjoy. Because I love autumn foliage & nature walks, I wanted to like this essay by @TomGilsonAuthor. But this is just plain silly.

This essay perfectly exemplifies the kind of bizarre reasoning that ID folks claim is open-mindedness about evidence for supernatural forces in nature. Let’s consider the ridiculous things that this claim requires (and add more to my list, please!)

First of all, leaf senescence is an intricately programmed process involving hundreds of genes. While it is most commonly associated with flowering plants (angiosperms), the genes and pathways for this process evolved in even older lineages of plant, before plants had colonized dry land, over 500 million years before Homo sapiens appeared. So… plants were engaging this process for 500 million years so that some humans could be treated to nice colors during their nature walks for a few weeks out of the year. Um, okay.

Sarcasm — “Um, okay” — is obviously no argument. Or if it is, it’s an argument from incredulity, and not his only one. I suppose it might seem to work if you already agree with him; if you beg the question, that is. If all this process of development went on over half a billion years with no planning, no foresight, no teleology involved, then “Um, okay,” would be quite an adequate refutation, and my point that fall colors are an intentional gift would be ridiculous. But that’s no better than saying, “If Gilson’s point is wrong, then it’s wrong.” True enough, except it assumes the conclusion; it begs the “if.”

Making Things Hard That Aren’t

Secondly, humans and their ancestors evolved almost exclusively in Africa for basically all of the last 20 million years. (Yes, waves of other hominids periodically left Africa but these were not our ancestors and probably had little appreciation for foliage.) Even our recent ancestry was almost exclusively in tropical and subtropical areas in which leaf senescence is not a thing. So… the design for fall colors could have been placed where humans were actually living for most of our history, but it wasn’t because… ?

Because there is nothing in the word “gift” that entails its having been given identically to all persons at all times. That’s not hard, actually.

And thirdly, even in modern times, the vast majority of humanity does not live in regions that exhibit anything like the autumn foliage that we see in parts of Europe, North America, and some parts of Central and East Asia. Brilliant and conspicuous leaf senescence occurs in a particular slice of where human beings live. So… this gift was not for all of humanity, but exclusively for those living in specific places. Lucky us!

Same answer. Again, not difficult.

Arguing from Incredulity

To believe this story (for which there is no evidence), you have to also believe that a supernatural power designed this little gift 500 millions years ahead of time, specifically for a minority of modern humans that would eventually live in a small slice of the world.

Here we have an argument from incredulity. It amounts to, “I can’t believe God would design something good for some people, and not give it to all people.” Why not? What kind of bland world would it be where everyone got all the same good things? What kind of impossible, contradictory world would it be where everyone got mountains, forests, oceanfront views, acres and acres of fertile fields, warm sun all year round, skiing and ice skating whenever you like, four seasons, no seasons …?

Different places have different advantages. You don’t get much by way of fall colors in coastal Orange County, California, where I once lived, but you do have near-ideal weather most of the year. Is that a design flaw? Nathan seems to assume that design means homogeneity. I have no idea where he gets that from. His objection is just thoughtless incredulity, as far as I can see.

False Dichotomy and Question-Begging

And fourthly, what about the actual function of leaf senescence for the plant? Was this just a side effect? In the view of Intelligent Design, everything else in nature was designed specifically for the pleasure and comfort of human beings. But here in the real world, we understand that living things have their own physiology that functions for their own purposes. Not everything is about us.

No, that’s not “in the view of Intelligent Design.” Sorry. It’s not even essential to my perspective on leaf coloration being a gift, for those who get to enjoy it. He’s set up a false dichotomy: Either living things have their own physiology and functions for their own purposes (his view) or nature is “designed specifically for the pleasure and comfort of human beings.” That’s a strange forced choice, and a fallacious one. In a theistic intelligent design viewpoint, things can have multiple ends or purposes. To deny that possibility is to beg the question again. It’s fallacious reasoning.

Besides just being comically unscientific, this particular kind of thinking, that humans are the center of everything and everything was designed with us in mind, has some pretty harmful consequences and corollaries.

If that’s supposed to count against the truth of my argument, it’s an argument from consequences, and fallacious on that count. I’m sure he’d object if I said evolution is false because “this particular kind of thinking, that humans have no purpose, has some pretty harmful consequences and corollaries.” I believe it does, but that’s not what makes it false.

Maybe he’s just raising a warning, though, as in, “Not only is this wrong, it’s also harmful.” That avoids the consequences fallacy. It’s still in error, though, because it depends on his jumping wildly to a conclusion that no one’s ever suggested, as far as I’m aware: That “humans are the center of everything and everything was designed with us in mind.” I don’t believe that for a moment, and neither does any other theist I know. (Intelligent design theory doesn’t entail theism, but a majority of ID supporters including myself are theists, and it’s the version of design theory I know best how to discuss.)

Rebutting What No One Believes

To be a theist, in fact, is to believe that God is the center of everything, and that some things he created with humans in mind. Christian theism in particular places humans in stewardship of the environment, giving us responsibility to care for it.

If he’s rebutting anything in this paragraph, he’s rebutting something no one believes. Why not? I’ll rebut it right along with him! I think it’s wrong, too, which is the same as saying I don’t believe it either. I’m not going to waste time doing it, though. Sure, I could go around knocking down beliefs no one holds, but if I’m going to while away the time with mind games that have no connection to the real world, I’d rather do it playing Sudoku instead.

And before you says this is just poetic, read the essay. He’s quite serious. And before you say this doesn’t represent ID, this is a featured article at “the intellectual home of Intelligent Design.” This is what passes for serious thought at the Discovery Institute.

The silliness of Intelligent Design is why no one takes their ideas seriously. But the harmful consequences is why we do take the movement seriously and why we take time from our other work to refute them at every turn.

Why They “Can’t Say the Trees Are Beautiful”

In a side conversation on Twitter, someone asked why I said, “The evolutionist cannot honestly and coherently say, ‘It’s glorious out there! The trees are beautiful.’” He wondered what I meant by “evolutionist.” I think that’s plain in context. In case it isn’t, I was talking about the person who believes in undirected, naturalistic evolution.

Nathan Lents answered him, “Maybe @TomGilsonAuthor can enlighten us as to why we can’t say the trees are beautiful.” I didn’t. I said they can’t say it honestly and coherently. If he wants to know why I said it, he can go back and read the reasoning in what I wrote there in the first place. If he thinks I’m wrong about it, he can probe with questions or objections.

Where Not to Find Serious Thought

There was no refutation here. It was all fallacious. Some of it was misdirected at things I didn’t say, some of it was question-begging. Some of it was making easy things hard, some was built on a false dichotomy. The rest? He was arguing from incredulity.

He mocks my essay as “what passes for serious thought,” but he does so by means of an extended series of logical fallacies. It doesn’t speak well of his standing as a critic of serious thought.

Does this by itself mean my essay is sound, rational, well-argued? No, actually, it doesn’t. I wasn’t even talking about it, really, but about Lents’s short Twitter article instead. It does mean, though, that to the extent that any problem with it may depend on Lents’s critique, it still stands solid. Sure, maybe someone will show that there’s a whole lot wrong with what I wrote. That’s an open question anyone can pursue. But not for Lents’s reasons, because they fail the test of valid reasoning.