Carrots, Eggs Coffee
clarkeching.com
clarkeching.com
The thing that always bothers me about these stories is how you could just as easily spin the negative foods into positives and come down hard on the 'good' one. Would you rather be like the carrots that began life rigid and inflexible but learned to adapt and become flexible and malleable; able to adapt to new situations? Or like the eggs, which started out fragile and easy to crack but found a hidden inner strength in adversity? Or are you going to be like coffee and totally decohere in the boiling water, ultimately losing your identity and becoming little more than vapor, able to be blown away by a strong breeze?
A good metaphor has an inner clarity that this just lacks.
It wasn't just that different things respond differently, it was that some things respond poorly and the beans respond well. But the metaphor only works if you accept the conclusions and don't try to examine it closer. For example, did either of the characters in the story taste the water? If the whole point is that the beans changed the character of the water, it does your metaphor a great disservice to ignore the fact that the carrots are going to change the flavor (admittedly it's not going to be as nice as the coffee, but it's the exact thing that the center of the parable hinges on).
As an example of what I think is a nicely constructed metaphor, look for the first metaphor in Book I of the Aeneid (too large to reproduce here, check out http://classics.mit.edu/Virgil/aeneid.1.i.html and search for "His finny coursers"). It comes in the scene where Poseidon is calming the seas of some rogue winds loosed by Aeolus, and compares him to a "grave and pious man" talking down a rioting crowd. The correspondence between the rioting crowd and the sea is intuitively clear, and the modern innovation of modeling crowd and traffic behavior with techniques from fluid dynamics serves to reinforce it. The image of calming the crowd with "sober words" lends insight into Poseidon's approach toward his domain. On a personal level it also invokes the story of Joshua Norton calming a San Francisco riot by reciting the Lord's Prayer in the street.
The point (which I've taken an awful long time to get to, I apologize) is that unclear and ambiguous metaphors tend in my experience to bely unclear thinking. When I can rewrite a story as I read it to have the opposite meaning as it was supposed to, it suggests to me that it was not written in the first place with a critical eye.
Virgil is a great choice for examples of metaphors that are well done. Your example is a good one, no argument there. Is the metaphor in the parable as tight as one written by Virgil? Certainly not. Indeed the line you quoted from the parable is a poor stylistic choice; it ties the reader in too closely with literal interpretation. However the central question that needs to be asked when examining any metaphor is this: was it effective in communicating to the reader the central message? I argue in this case yes. When I read it, I didn't get tied up in the specifics of the food. My thought process was this: (1) Three objects placed in boiling water (2) Outcomes are all different (3) Some outcomes are good, some outcomes are bad (4) All the objects are food, why are the outcomes different? (5) The internal characteristics of the food led to different outcomes (6) Perhaps the internal characteristics of a human being could lead to different outcomes.
If the metaphor wasn't tight enough for your liking, that's ok! Personally, I don't have the same expectations from a piece on the internet and a piece by Virgil. The metaphor was good enough to get the job done for me, but I certainly wont argue with you if you refuse to accept it. :)
The main area where I disagree with you is when you say: When I can rewrite a story as I read it to have the opposite meaning as it was supposed to, it suggests to me that it was not written in the first place with a critical eye. My point is that your rewritten version actually means the same thing as the original. I don't think the story has anything to do with coffee beans in the literal sense. The writer could have used lobsters. ;)
But this story was purely constructed, ambiguous, trite and completely without character.
We don't do parables too often here at HN; a clever one making it to the front page one every half-year seems worthwhile to me. Some people find them to be useful mental tools. Others use them as launching points for new ideas. Still others use them as a trigger to reflect back on past strategies. In low dosages, they can serve a purpose. I liked this one, and I wont vote for something like it for a long time.