Part 1
Well, I can see some problems with your definition.
Hypothetically, suppose we met a bunch of intelligent space aliens that could discuss poetry with us and play chess with us, but had a different basis for their biology, no DNA, no ATP. According to your definition, they're not alive. They're not as alive as a bacterium. They're as alive as a rock, i.e. not alive. They don't use ATP.
But surely a definition of life should include them?
By analogy, imagine an island where a bunch of white people live, and where all the animals are black. Now, these islanders might come up with a definition of human that says: "Humans are white, anything that's black is a mere animal". But their definition is parochial, it only works for their particular island in the particular time that they're inhabiting it.
A definition of life has to include everything that we'd acknowledge as being alive if we saw it.
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Part 2
You say that scientists equivocate over the definition of life. No they don't. A true statement would be: different scientists offer different definitions of life. None of these definitions are equivocal, they're just different. Now you've offered one more different definition. According to your idea of what makes scientist equivocal, you would just have made scientists
more equivocal, if only you were a scientist.
Let's try to think of an analogy ... let's say a Japanese person has a strong opinion on whether or not gay marriage should be legal in America. He proposes that gay marriage should be legal in America if and only if the people involved are over the age of forty. Here (he says) he has a clear and unequivocal rule, whereas
Americans are so equivocal. Why do they equivocate so much?
But no particular American is equivocating. Some of them say YES, some of them say NO, some say that they haven't made up their minds yet, but none of them
equivocate. The Japanese guy gets to say that Americans have "equivocal" ideas because different Americans have different ideas, whereas this
one Japanese guy has just one very clear idea. He's not equivocal, unlike all those equivocal Americans. And he condemns Americans for equivocating about gay marriage, whereas
he has one simple unequivocal idea about gay marriage, which makes him less equivocal and more honest than all those dishonest equivocating Americans, who are collectively equivocating.
But he would actually be
adding to the American "equivocation" about gay marriage if he was American. In the same way, you would be adding to the "equivocation" of scientists about the definition of life if only you were a scientist.
Well, it's easy to be "unequivocal" if you're just
one person. Any group of people is going to be more equivocal. 'Cos of them being more than one person.
You see why this Japanese guy would be stupid?