6 ms·

What about strategies that involve blowing up the bridge instead of one of the islands? This seems much more real world feasible.

sthnblllII 6y ago
Because the bridge is a metaphor for trade so thats the same thing as just choosing not to trade.
whack 6y ago
> What about strategies that involve blowing up the bridge This sounds like the cornerstone of Trump's trade policy. "Give me what I want, or I will end all trade between us." In theory, it works. In practice, you end up with a Dr Strangelove dystopian outcome.
- redis_mlc 6y ago
  > This sounds like the cornerstone of Trump's trade policy. Nope, Trump's trade policy is based on reciprocity.
pdonis 6y ago
> What about strategies that involve blowing up the bridge The article rules those out by presenting scenarios in which there is always some advantage to trade. In any such scenario, neither party has any incentive to blow up the bridge, since there is always some way for each party to improve their situation by using the bridge to trade, compared to what their situation would be if the bridge did not exist. In the real world, there are cases where there is no advantage to trade, usually because one or more of the "complexities" described in section III of the article applies. The obvious one, of course, is "there might be more than two people"--in the real world, there are always more than two parties with whom potential trades can be made (this is true even if we consider the "parties" to be nations instead of individuals), and as the article notes, in that case there can be scenarios where at least one party will gain nothing from trade.
- nautilus12 6y ago
  But can't you leverage cutting off trade in the same way that he talks about threatening to blow up your island, and it wouldn't result in total loss of everything (which any rational player would see through as a bluff, as opposed to losing trade which would be a negative but still survivable). IE think about the modal logic intersected with the game theory, no one will believe that you will blow up your own island, but they may believe that you will blow up the bridge.
  - pdonis 6y ago
    > can't you leverage cutting off trade in the same way that he talks about threatening to blow up your island If you are the only possible party the other party can trade with, then blowing up the bridge and blowing up your own island are, as far as the other party is concerned, equivalent, yes. So if there is any benefit to the other party in trading with you, they have an incentive to have that trade available to them, and hence to do whatever it takes to have you not blow up either your own island or the bridge. However, if there are any other parties besides you that can be traded with, that is no longer the case, because you not being there just means they go trade with someone else. Another thing to note is that the article's assumption of non-violence, which basically means neither party will do anything to harm anything that isn't their own property, also rules out blowing up the bridge, since the bridge, by hypothesis, is not the property of either party. A better analogy to withholding trade in the article's scenario would be something like building an impenetrable wall at your end of the bridge.
    - nautilus12 6y ago
      I'm not sure you are following my point though, whether its blowing up a bridge or building a wall, if you look at the payout to the party that is blocking it is higher than blowing up the island. If you then use modal logic to analyze the opposite parties perspective of whether or not that party would actually go through with it then their threat seems much more believable.
      - 6y ago
bluGill 6y ago
Once I realize there is a possible trade I can make a boat, or swim. The bridge is the easiest way, and allows us to ignore the (very real) cost of transport in this example. In the real world most trade involves third party delivery companies with trucks, trains, or boats.

sthnblllII 6y ago

Because the bridge is a metaphor for trade so thats the same thing as just choosing not to trade.

whack 6y ago

> What about strategies that involve blowing up the bridge This sounds like the cornerstone of Trump's trade policy. "Give me what I want, or I will end all trade between us." In theory, it works. In practice, you end up with a Dr Strangelove dystopian outcome.

redis_mlc 6y ago
> This sounds like the cornerstone of Trump's trade policy. Nope, Trump's trade policy is based on reciprocity.

pdonis 6y ago

> What about strategies that involve blowing up the bridge The article rules those out by presenting scenarios in which there is always some advantage to trade. In any such scenario, neither party has any incentive to blow up the bridge, since there is always some way for each party to improve their situation by using the bridge to trade, compared to what their situation would be if the bridge did not exist. In the real world, there are cases where there is no advantage to trade, usually because one or more of the "complexities" described in section III of the article applies. The obvious one, of course, is "there might be more than two people"--in the real world, there are always more than two parties with whom potential trades can be made (this is true even if we consider the "parties" to be nations instead of individuals), and as the article notes, in that case there can be scenarios where at least one party will gain nothing from trade.

nautilus12 6y ago
But can't you leverage cutting off trade in the same way that he talks about threatening to blow up your island, and it wouldn't result in total loss of everything (which any rational player would see through as a bluff, as opposed to losing trade which would be a negative but still survivable). IE think about the modal logic intersected with the game theory, no one will believe that you will blow up your own island, but they may believe that you will blow up the bridge.
- pdonis 6y ago
  > can't you leverage cutting off trade in the same way that he talks about threatening to blow up your island If you are the only possible party the other party can trade with, then blowing up the bridge and blowing up your own island are, as far as the other party is concerned, equivalent, yes. So if there is any benefit to the other party in trading with you, they have an incentive to have that trade available to them, and hence to do whatever it takes to have you not blow up either your own island or the bridge. However, if there are any other parties besides you that can be traded with, that is no longer the case, because you not being there just means they go trade with someone else. Another thing to note is that the article's assumption of non-violence, which basically means neither party will do anything to harm anything that isn't their own property, also rules out blowing up the bridge, since the bridge, by hypothesis, is not the property of either party. A better analogy to withholding trade in the article's scenario would be something like building an impenetrable wall at your end of the bridge.
  - nautilus12 6y ago
    I'm not sure you are following my point though, whether its blowing up a bridge or building a wall, if you look at the payout to the party that is blocking it is higher than blowing up the island. If you then use modal logic to analyze the opposite parties perspective of whether or not that party would actually go through with it then their threat seems much more believable.
    - 6y ago

bluGill 6y ago

Once I realize there is a possible trade I can make a boat, or swim. The bridge is the easiest way, and allows us to ignore the (very real) cost of transport in this example. In the real world most trade involves third party delivery companies with trucks, trains, or boats.