In defense of twocows' view, here's a little reductio ad absurdum analogy:
Jack and Jim are siblings living with an abusive parent, who provides for them as shelter a run-down, cold, and musky shack that is entirely too small for even one person to live in, let alone two. For food, the brothers rummage through the neighbors' compost bins for edible scraps, which is just barely enough to them keep from starvation. On a lucky day, they would occasion upon a half-gnawed apple core with plenty of the juicy flesh left behind by a lazy eater, which they would split in half and savor delicately. During rainy days they would step out of their hut and open their mouths skywards, so as to catch a few replenishing drops of rain.
Now, Jack and Jim's parent was quite fond of drinking, and from time to time in a drunken rage he would go down to their little shack and beat them both until they were bleeding and lying unconscious on the floor.
The years pass, and the siblings (against all odds!) have grown stronger and smarter, and they contemplate leaving their parent's custody to make their way in the world. Jack is enthusiastic about the idea, but Jim disagrees. "Well, gee, Jack-- it's a big scary world out there; maybe we would be safer staying in our shack than going out," he says.
"I mean," he goes on, "it's not all too bad when you think about it; there are days when we get to eat apples and on some weeks our parent doesn't break our bones."
"Going out into the world and trying to make a living there-- isn't that like pretending to be an adult (playing God)?"
Jack tried his utmost best to convince his sibling, but to no avail. He left one chill September day, taking with him what little possessions he had, and never looked back since.
Two years later, Jim's thin, beaten-up, malnourished corpse was found in the brothers' old shack. His parent was on a particularly passionate rage one night and accidentally (?) cut his carotid artery.
So it goes.
The 'parent' here is 'nature', and those who defend the irrationality of external circumstances that trample upon the dignity of mankind are the Jims. The world is cruel, evil, and indifferent to human suffering. That is a fact. What is really odd here is that there are Stockholm syndrome victims here that actually think that this is a good thing.
RECOMMENDED READING: von Goethe, Johann Wolfgang:
Prometheus (1789)
Oh, and clones! So that I don't stray too far from topic, here's a remark about clones!
If you try to 'dehumanize' a clone, who looks, thinks, and acts like a human, then you're already committing a major moral offense. The fact that the subject of dehumanization is a copy of someone else-- how does that matter? People who are capable of doing this are probably already capable of dehumanizing non-cloned humans anyhow-- the problem is nothing new, in other words.
e.g., third-world plantation laborers, Chinese sweat-shop workers, etc.