Post Author: Bill Pratt

In the first two parts of this series, I presented Mark Isaak’s arguments from his 2003 article.  In this article, his central contention was that human design and life are not analogous; there are at least six important differences that make the analogy break down.

Analogies imply that there are similarities and differences between two things.  An analogy works if the similarities outweigh the differences, or if the similarities are in the essential properties of the two things and the differences are in the accidental properties of the two things. I recap below each point Isaak made:

1. Human design includes blueprints, tools, and other evidence of the design process.  Life shows no evidence of a design process.

I argued that actually possessing evidence of a design process is not an essential property of making an inference to human design.  Additionally, since Isaak wrote his article, we do see the design process in labs that are designing artificial life forms, which weakens Isaak’s point further.

2. Human designs display simple organization.  Life displays complex organization and intermodular interdependence.

I argued that simple organization is not an essential property of human design.  In fact, the more complex human designs are, the more likely we are to attribute design.

3. Human designs are manufactured.  Life is characterized by reproduction, growth, and development.

I argued that manufacturing which excludes self-replication is not an essential property of human design.  After all, we have examples of human designers combining self-replication and manufacturing processes.

4. Human designs are generally repaired from the outside.  Life is self-healing, at least in part.

I argued that human designs are not always repaired from the outside, and that this is therefore not an essential atrribute of human design.

5. In human design form follows function.  In life, forms follow nested hierarchy.

I argued that human design does not always have form following function, and therefore this attribute of human design is not essential.

6. In human design, there is rapid change.  In life, there is slow change.

I argued that human designs change both rapidly and slowly, so rapid change cannot be an essential attribute of human design.

After examining all of Isaak’s differences between human design and life, it seems to me that he has not made the case that life does not look designed.  He has identified accidental or secondary attributes of some human designs, but claimed that these are essential or primary attributes of all human design.

Where does this leave us?  It convinces me that the design argument from analogy is a live option.  Arguments from analogy are never certain, but as scientists continue to make technological advances of the kind Craig Venter’s team is making, I see the design argument from analogy only getting stronger.