Life #3 - Lack of Definition

In the last blog in the series, let us look at different perspectives on the lack of definition for the term “life”, from Carl Zimmer’s Life’s Edge. One view is the one expressed by Radu Popa:

“A science in which the most important object has no definition? That’s absolutely unacceptable.”

 

Others don’t see a problem. Let each set (NASA, microbiologists, physicians) have their own definition, they say – its impact, in any case, is limited to their area of research. As you might have imagined, not everyone takes that view.

 

Some philosophers point out that so many day to day terms have no definition either, yet we use them without confusion. Ludwig Wittgenstein asked:

“How, for example, would you answer the question, “What are games?”

Games. Some have winners and losers, others don’t. Some have tokens, others card, and yet other tools in other games. For some games, the players get paid; for others, they pay to play. And yet, as Zimmer points out:

“However, we never get tripped up talking about games. Toy stores are full of games for sale, and yet you never see children staring at them in bafflement. Games are not a mystery, Wittgenstein argued, because they share a kind of family resemblance.”

 

Maybe, says Zimmer, the lack of a definition of life is a sign that biology is like chemistry, before it entered the modern age. Once upon a time, alchemists and chemists tried to define water by its characteristics – liquid, clear, solvent etc. This only created more confusion, because those descriptions were met by many acids! The problem, as we learnt only when chemistry advanced, was that those early folks didn’t know the concept of atoms, molecules and chemical formulae. But even that isn’t enough. H2O, for example, doesn’t define water. After all, a single molecule of water cannot exhibit the properties of water. How, for example, can anything dissolve in a single molecule of anything else?

 

Which is why Zimmmer feels that biology may be in its infancy, the way chemistry was in the example above.

“Theories don’t pop into existence. They only emerge after scientists have carried out lots of tedious experiments of the world.”

As he says, only when chemists noticed through “tedious experiments” that the ratios of elements in compounds seemed to always be in integers, could they begin to guess about the concept of atoms and molecules.

“Some scientists today believe that a theory of life can emerge only from exacting measurements of living things.”

 

Will biology eventually be able to frame a definition for life? Only time will tell.