What is "Life" anyway?

In my last post, I proposed that we need to re-examine how life emerged from non-life some time in the past. But what do we mean "life"? What trait distinguishes the living from the non-living? If we are going to investigate how life emerged, we need to understand what it is we are investigating. Despite the broad use of the terms and apparent self-evidence of a definition of "living", it is, in fact, very difficult to state with scientific rigor a definition that does not bring with it, some presupposition about the nature of living things.

In the past, something was only considered to be alive, if it was able to move on its own. This eliminated the entire plant word from consideration. In a similar vein, respiration, the consumption of food and production of waste, seem ill adapted, as this eliminates viruses, which are arguably, one of the most virulent forms of life on the planet.

I propose a very simple definition: "A system is considered to be a living system, if in the general case, members of the system class possess the ability to produce another distinct living system." Despite the obvious self referential nature of this definition, it is the very reproductive capability of life that makes it unique. All other chemical processes pale in comparison to the process by which one living thing creates another distinct version of itself.

The definition makes a few very important distinctions. First, the general case for a class of systems (individuals sharing a set of traits) is key to whether or not a system can be considered living. If the normal state of members of the class is the ability to reproduce, then an individual within the class which cannot reproduce may be considered living by virtue of its membership in the class.

Second, no requirement exists for a living system to produce a copy of itself or even of a system similar to itself. All that is required is that the system produce another system capable of producing another system. In this way, both evolutionary and species stable models of life's origins can be considered.

Lastly, this definition implies nothing about the source of the system. Whether the system was produced by naturally occurring means, or as the result of intelligent, directed efforts (e.g., man-made), it has no bearing on consideration whether the system is living. Some may believe that this omission invalidates the definition, but I would argue that understanding living systems that are designed is critical to understanding living systems that exists apparently without a designer.

How life began is still unproven!

How did life begin? It's a simple question. It assumes only two things, that life exists now and that it didn't at some time in the past. For such a simple question, with so little to define before exploring the possibilites, why is it that after 5,000 years of recorded history and 300 years of dedicated scientific study, we still can't answer it with scientific proof?

I think that the main problem is we abandoned the question a long time ago. Instead we assume our answer to the question is correct and interpret everything else in light of that answer.

Both Evolutionists and Creationists fail to unbiasedly approach the study of how life first formed. Perhaps the evolutionist considers the emergence of life from non-living materials a settled issue. But until the mechanism for abiogenesis is discovered and proven, the question of how life emerged is still open. I am not denying the possibility that life appeared in this way, but until the mechanism can be demonstrated, to act as if the question is closed is nothing more than an assumption and should be viewed as such.

Creationists are no less guilty of approaching the topic with bias and predetermined conclusions. In fact, many creationishts make the scientifically unfounded assumption that life cannot arise naturalistically and spontaneously. Yet the only proof they offer is the lack of proof that life did arise from non-living materials. And when they are confronted by this, they hide behind this statement: "Since the creation of life was a unique and supernatural event, there is no scientifically valid method for proving special creation." Frankly, this is a cop-out! Everyday, we make judgments concerning the origin of things around us, deciding whether an item was produced by naturalistic means, or by a conscious, creative act. Authors have been identified from their work, because structure and nature of the work leaves evidence of the author within the text itself. How much more should there be observable evidence throughout creation that testifies to life's author.

The emergence of living things is probably one of the most amazing and least understood things in the universe. The only way we are ever going to get to the bottom of the question (scientifically speaking), is if people on both sides of the Creation/Evolution debate find a way to work together and share their research. And it is not enough to work together on "common ground" we have to work together on the most contentious problems. When each side brings its perspective to the issue and the other listens and considers how it fits within his own perspective can we achive the catalyst of knowledge that may allow us to crack the question and truly answer, scientfically and definitively how life emerged.