Am marking the essay, "Greed is good." Comment. A nice, open-ended question. The instruction to "comment" leaves the essayist a lot of room to explore the concept of Greed, and its effects on us as a people, and its impact on the world. But because the discussion could literally go anywhere, it's of vital importance that the essayist nails down a clear definition of Greed and use that definition as a standard of comparison in order to determine just how good greed is.
For a more interesting discussion, we might want to define greed as an extreme form of human behaviour. We are looking for a clash of ideas, else an argument wouldn't be an argument otherwise.
If greed is extreme, then greed goes beyond the desire for more, and for better -- which, unfortunately, most of the essays I'm marking tend to stop at. Everyone wants more, everyone wants better, so what makes the greedy stand out? Greed pushes the limits of what is normally acceptable, tolerable and reasonable, in terms of quantity desired, and in terms of the methods by which such desires are satisfied, usually at the expense of other people.
So to answer the question, the essay must provide yardsticks (e.g., moral or religious) by which to determine the difference between normal, acceptable desire and that which goes beyond the pale, i.e., greed.
The essay should explain why people generally take a dim view of greed, but more importantly, show that there is a direct relationship between this extreme behaviour and the harm it brings as a consequence. There needs to be sufficient supporting evidence illustrating this cause-effect so that we can draw specific principles about greed from the examples cited.
But according to the question, greed is good, so how can this be? "Good" suggests that there is some benefit to be derived from greed despite its negative consequences. Again, the discussion needs to show a causual link between greed and specific (though perhaps unintended) benefits accruing to the individual or to larger society. Again, with the use of supporting evidence to back up the claim.
Now we have a clash of the negative and positive effects of greed, but to leave the discussion like this is neither instructional nor helpful to our understanding of greed. It's balanced, but boring.
A little insight would help spice things up a bit. Perhaps we could say that although greed generally leads us to some very negative consequences, greed is still an essential trait in people because it shows us that there is more to achieve in life, to push beyond our current limitations and makes us innovate and stretch ourselves to reach that which was once unreachable. Such has been the process of human progress. It is how we have thrived as a species and have come to dominate life on this planet... But at our current level of progress, can our planet sustain any more of our greed, or do we need to find a new way to progress before our greed kills us all? (Haha, how drama)!
Something like that.