Volume 1, Issue 1 
1st Quarter, 2006


Astrobiology: What Are the Characteristics of Life?

Barry Blumberg, Ph.D.

Page 3 of 7

How Do You Define Life?
I think the answer to defining life is that there isn't a definition. My guess is there never will be, but there will be a set of characteristics that can become generally accepted. In the study of biology, there are many questions of this nature and there isn't a real definition, but a sort of consensus. Answering the question, "what is life?", is a complicated undertaking and different approaches are required. I'm going to talk about the scientific approach, but it's obviously of interest in religion as well. In most cultures, religions have creation stories. Some of them are absolutely fascinating. And it's a philosophical issue; it's an ethical issue; it’s a legal issue. What is alive and what is not? And of course there are a lot of politics involved in decisions about life. Approaching the question from a scientific point of view doesn't exclude these other considerations. 

Schrodinger’s “What is Life?”
I first want to talk about the book, What is Life?, written by Schrodinger in 1944. It generated an enormous amount of interest.  I have a copy of this book from 1945 that I got when I started graduate work in mathematics and physics.  I'm not sure that I actually read it, because usually I write in books when I read them, and so I have a horrible feeling that I may not have. This book influenced a lot of people, particularly physicists, with the notion that you could explain life based on physics and chemistry. The argument is that physics is based on math; chemistry is based on physics; and biology is based on chemistry, physics, and math. 

The Elan Vital
The notion used to be that you could explain all of life by explaining a series of quasi-mechanical processes - chemical processes that take place within the cell, within an organism - and you add all those up and that's going to tell you about life. But that excludes this kind of semi-mystical view of life that defies scientific description - the idea of a life force - the élan vital. This is the notion that there are all of these things, but they take some kind of spark to get going.

All of you will remember a brilliant novel by Mary Shelley about Victor Frankenstein. When Victor makes the creature, he uses a spark of electricity. And when they made Dolly - the clone of a sheep - they decided to give it a little jolt of electricity to bring the egg together and I asked why.  Apparently, they thought it was a good idea to do that. So right now, I think the élan vital contemporary basis is complexity - the notion that what's embodied in the idea of complexity gives this extra kick that makes life. This is the equivalent of the electric spark that Victor Frankenstein used.

The extension of this is molecular biology, which has contributed enormously to understanding, at a molecular level, the interactions that take place. And so you can explain things at a very detailed, high resolution area. You have the notion that some kind of quantum explanations of biological events are indicated. This notion holds that you can explain life by explaining various chemical and physical processes and when you all add them all up, it spells "mother."  

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