What is life, O Gentle Reader? What exactly is it? Is it merely a collection of chemical reactions in cells? Or is it, at the other extreme, some mystical force animating everything? I am sorry to speak in such clichés, but needs must.

We know almost all the chemical reactions in cells and have characterized almost all of the complex metabolic pathways. We have sequenced the genome. But why is it that, far from being able to synthesize a highly differentiated human cell, we have consistently failed to make something as simple as a bacterium, starting from scratch. We can modify existing cells and can even turn a hapless bacterium into a factory in microcosm, churning out molecules we need. But why do we not know what life is?

There are so many definitions of life. Life, according to some authorities is any focal region where entropy is reduced at the expense of an increase in entropy elsewhere. (Of course, then, a refrigerator is also alive!). But this much is true, if this entropy business stops, then an organism is dead. Entropy itself is a measure of the randomness or disorder of a system. Way back when, just before the big bang happened, the universe was in perfect order. This is when time did not exist, and (this is what will astound you), at this point there was no space either. And ever since then, we have been sliding for eons into chaos, from highly ordered matter into evanescent energy.

And are we merely machines programmed to sustain ourselves and replicate? Is that the purpose of life, to perpetuate itself? Or is it worse, something entirely without purpose, a cosmic accident?

A team of Russian scientists once tried to make a cell, ab initio. They made little semipermeable lipoprotein packets, and put synthesized enzymes in them. Then they put them all in another semipermeable packet, and adjusted the ionic concentrations and the voltage, put in microtubules, enzymes, and replicated, in short, the cellular environment. But the cell would not function. It lay in its fluid, an obstinate, albeit flaccid little bag. It would not live.

The tiny anthrax bacillus spore, something which is technically alive, can survive in soil, with the miniscule amount of food it has inside it, for 60 years, when the average time for which one bacillus exists as an individual, is about twenty minutes. That is like a human being living for, I don’t know, you do the math. And yet when it finds a collection of things I can only term hope, it burgeons into something beautiful: something alive.

So what is life? I want to know. I need to know.

What is it to be alive?