Is artificial life really life or not? I define Artificial Life as a &quot;simulation&quot; or &quot;copy&quot; of life. However, should it be considered a simulation or copy?
If one had motivation and money, someone could theoretically create evolving computers, with a program that allows mutation OR simply a &quot;simulated&quot; environment with &quot;simulated&quot; organisms.
The computer (or &quot;simulated&quot; organism) would have the ability to reproduce, grow, and take in energy. What if the life evolved to have intelligence? Currently, there are some relatively limited programs that simulate life, but most of them are heavily simplistic. Are they life?
When should something be called life?
If you read Steven Levy's book, Artificial Life,you will find, as I did, 



the distinction between biological and "artificial" life blurred. If you think about it, what exactly is "life", anyway? A set of complex systems with emergent behavior capable of evolution and adaptation.

A prototypical biologist may not define life that way. Indeed, he would, not being focused or concerned with the computational aspect, define it in a way that would narrow it down to biological life.

Marvin Minsky mention the concept of luggage words, and I myself came up with the notion of mirage concepts. For the former, that which we don't understand gets lump into the word. For the latter, when you take a "mysterious" concept apart, it vanishes like a mirage does as you get closer.

So what is life? If we look at a "living" organism, we'd all that "life". If we remove a single cell from that organism, we'd still call that "life". But what if we remove a single organelle like, say, a ribosome? Lysosome? Contractile vacuole? Endoplasmic reticulum? Is that still "life"? What if we remove a macromolecule from that? Is that still "life"?

As you see, all becomes very murky, and I do this on purpose to illustrate just how arbitrary the very concept of "life" is.

So I think my definition is a good one, broad enough to encompass both in-silico and the organic versions. It bespeaks to algorithms, robots, viruses -- yes both computer and organic... anything that has complexity and the ability to adapt and evolve.