When examining a death scene to determine if it was the result of accidental (or natural) causes or the malicious consequence of a killer, I begin by looking for evidence of intelligent interaction. Is there evidence at the scene that indicates another intelligent being (the killer) was present? In a similar way, when examining biological structures to determine if they are the result of accidental or natural causes, or the conscious consequence of an intelligent designer, I begin by looking for evidence of intelligent interaction. What are the features of design that all of us recognize intuitively every day, and are these features present in biological organisms? Here are three evidences I’m looking for in my investigation:
Evidence of Improbability Rather Than Probability
Could the forces of natural law alone account for what I am seeing in biology, and if so, is there enough time in the history of this organism for such laws to cause this result? Given nothing but matter, time and the unguided forces of nature, could simply proteins arise from amino acids? Could amino acids arise in the first place? Has enough time passed in the history of the planet for such unguided processes to account for the complexity we see in even the “simplest” organisms? How probable is such a hypothesis? As evidence for biological complexity mounts, naturalistic, unguided processes seem less and less probable.
Evidence of Irreducibility Rather Than Reducibility
If “natural selection” is true, each organism retains beneficial (unguided) mutations if, and only if, they benefit the organism’s ability to survive. Structures within each organism are therefore built through a process of addition, moving from simplicity to complexity if, and only if, the additions result in something beneficial:
“If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive slight modifications, my theory would break down.” (Charles Darwin in Origin of Species)
If we find structures within an organism (such as Michael Behe’s observation of the Bacterial Flagellum) that cannot have been formed slowly over time through a succession of slight modifications, there is good reason to believe the structure must have been designed. Examples of irreducible complexity in which a large number of proteins must come into existence in precise relationship with one another all at once, are highly improbable unless the assembly was facilitated by an intelligent agent who assembled the required pieces simultaneously. There are several examples of irreducible complexity in biology.
Evidence of Specificity Rather Than Randomness
When something is “specific”, it is “special, distinct, unique, particularly fitted to a use or purpose”. Information demonstrates specificity in its capacity to communicate specific ideas and concepts. As Stephen C. Meyer describes in Signature in the Cell, there isn’t a single example anywhere in the history of the universe in which information came from anything other than an intelligent source. Information is coded by the writer and decoded by the reader; when we see specific information, we can trust that an intelligent writer is involved. When we see information in DNA, guiding the formation of proteins and molecular machines within organisms, the most reasonable inference is the existence of an intelligent writer.
There seems to be plenty of evidence that an intelligent agent has interacted with the biological world with which we are so familiar. The most reasonable inference from the evidence of improbability, irreducibility and specificity is that our world is the product of intelligent design.