Does the information and machinery of life point to design?
DNA carries instructions, and living cells contain machinery whose parts work together. Do those features point to a Designer?
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Consider how the universe and living things are ordered, and whether intelligence best explains them.
The last lesson looked at the conditions that allow life to exist. Now look inside a living cell. Does the information in DNA and the machinery that uses it give us further evidence of design?
A note and a cell
A few days after your conversation about the stars, Jordan mentions a video he watched about DNA. “I understand why you think the universe looks designed,” he says, “but DNA is just chemicals, right?”
“Suppose you came home and found a note that said, ‘Dinner is in the fridge,’” you say. “Would you think somebody wrote it?”
Jordan laughs. “Obviously. It's a message.” He looks at you. “I see where you're going, but DNA isn't somebody writing sentences.”
“Fair enough,” you say. “What makes the note different from letters scattered across the counter?”
“The letters actually say something,” Jordan replies. “But mutations can change DNA, can't they?” He pauses. “And before there was anything alive to change, how did the first living thing get here?”
DNA carries information that cells use, and the machinery inside them depends on parts working together. We know intelligence can produce instructions and build machines, which gives us good reason to see a Designer behind life.
The universe has the conditions needed for life. But how did the first living system begin, and what explains the instructions and working machinery we find inside cells?
Where did life's information and machinery come from?
Think back to the note about dinner being in the fridge. You would know somebody wrote it because the letters form a message. We recognize that kind of arrangement as the work of a mind.
Now consider DNA. The order of its four bases matters because cells use those sequences to make proteins and control when they are made. The cell has machinery that copies and reads those instructions. Change the sequence, and you can change what the cell produces. The chemicals carry information that the cell actually uses.
We know intelligence can produce instructions, write code, and put machines together for a purpose. Stephen Meyer argues that intelligence is the best explanation for the origin of the biological information life depends on. That raises a question about the beginning of life itself: where did the first living system get the information it needed?
How did life begin in the first place? Scientists have proposed ways that nonliving chemistry might have led to life, and laboratory experiments have reproduced some possible steps. But no complete proposal has been established as the route life actually took. That uncertainty does not prove design. A laboratory experiment can show that a chemical process works under certain conditions. The fact that researchers arranged those conditions does not mean the chemistry could never occur naturally. We still have to compare the proposed natural routes with intelligent design and ask which explanation accounts for the information, copying, and reproduction required by the earliest living systems.
The machinery inside cells gives us another reason to think about design. The bacterial flagellum is a tiny motor that helps certain bacteria move. A rotating motor, a hook, and a long filament work together to propel the bacterium.
Michael Behe uses the term irreducible complexity for systems whose present function depends on several parts working together. Remove an essential part of the flagellum, and the motor stops doing its job. Behe asks how these parts could have come together without a plan. Researchers have proposed earlier stages in which some components served different functions, and certain flagellar parts resemble those in other bacterial systems. The design argument has to address those proposals. The fact that the motor needs several parts today does not establish that earlier stages could not have functioned differently.
We know minds can produce instructions and working machines, and we've already considered reasons for believing in an intelligent Creator. That is why I see design as a serious explanation for life's information and machinery. The competing natural explanations still deserve to be tested.
Bottom line: Living cells contain instructions and coordinated machinery, and we know intelligence can produce both. The origin of the first living system raises the question of how information and reproduction began at all. Given the earlier reasons for believing in a Creator, I believe the information and machinery of life point toward intentional design.
Think about it: If researchers eventually produced life from nonliving materials in a lab, what would they have shown?
Where did those systems come from?
Jordan thinks back to the note. “So DNA is not literally English. You are saying the order carries information the cell actually uses.”
“Right. And intelligence is something we already know can produce instructions and coordinated machines.”
You talk through the first-life problem and the flagellum again, including why laboratory work can show what chemistry is capable of without automatically showing that the first life arose without guidance.
Jordan nods slowly. “The information part is stronger than I expected. I am not ready to say every question in biology is settled, but I see why a mind belongs in the discussion instead of being ruled out from the start.”
He glances toward the intersection ahead. “So you think the same Creator also explains things that are not physical, like right and wrong?”
Use what you learned in a different situation
A friend says, “Scientists are trying to make life from scratch in a lab. If they succeed, won't that show how life began without a Creator?” How would you answer?
The full course lets you write your response, compare it with a model, and track your progress.
Practice this inside the full courseQuestions this argument still has to face
“DNA is made of chemicals. Why call it information?”
Cells use the order of DNA's bases to make proteins and regulate other functions. The note on the fridge helps us see why the arrangement of ordinary materials can matter. DNA isn't a sentence, but its sequence has a real biological function.
“Mutation and natural selection can produce new genetic information.”
They can produce changes in organisms that already reproduce. The origin-of-life question goes further back: how did the first system capable of preserving and passing on information arise?
“Scientists have proposed ways life might have come from nonliving chemicals.”
They have, and researchers have demonstrated some chemical steps. What they have not established is a complete pathway shown to be the one by which the first living system actually arose. The origin of information and reproduction still needs explaining.
“If scientists make life in a laboratory, wouldn't that settle the question?”
It would show that intelligent researchers assembled life under conditions they selected. It might also show that those chemical steps are possible. It would not, on its own, tell us whether the first living thing arose through the same steps without anyone arranging the conditions.
“Some parts of the flagellum could have served other functions.”
Some flagellar components resemble parts of other bacterial systems, and researchers have proposed evolutionary paths using components with earlier functions. Those proposals deserve examination. The design argument needs to show why those pathways are insufficient and why intelligent causation fits the evidence better.
Use this in a real conversation
- Use the note on the fridge first. Explain why we recognize a writer, then show how the order of DNA's bases matters to a cell.
- Connect DNA to the first living system. Scientists have suggested pathways from chemistry to life, but none has been established as the route life actually took.
- Explain what laboratory experiments can show. Researchers choose the materials and conditions; even a successful result would not, on its own, establish what happened without guidance in the past.
- Distinguish life's beginning from changes in organisms that already reproduce.
- Use the flagellum to explain Behe's argument from coordinated machinery. Finish by connecting the evidence back to the earlier case for a rational Creator.
The note illustrates how information can point to intelligence without making DNA identical to human language. Early life need not have resembled today's DNA-based cells. Lab experiments can test whether particular chemical steps work, while the historical route to the first life remains unresolved. Behe's flagellum argument should be examined on its evidence.
Sources for further study
- Stephen C. Meyer | Signature in the Cell: The DNA Enigma: Develops the positive case for intelligence as the source of the information required by the first living systems.
- Michael J. Behe | Evidence for Intelligent Design from Biochemistry: Introduces irreducible complexity and the challenge posed by tightly coordinated biological systems.
- Michael J. Behe | A Mousetrap Defended: Clarifies his argument about how an entire working system could develop through gradual steps.
- National Human Genome Research Institute | DNA Fact Sheet: Explains how DNA carries instructions for making proteins and regulating their production.
- Discovery Institute | Responding to Criticisms of Irreducible Complexity: Addresses the objection that finding another use for one component explains the origin of the whole flagellum.
- Fletcher, Diggines & Elani | Molecular systems engineering of synthetic cells: Reviews how researchers design and assemble artificial cell systems in the laboratory and the challenges that remain.
- Pallen and Matzke | Evolutionary Origin of the Bacterial Flagellum: Presents an evolutionary account involving component reuse and earlier functions, allowing a direct comparison with Behe's challenge.
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