Merriam Webster Online Dictionary
Main Entry: zero-sum
Function: adjective
: of, relating to, or being a situation (as a game or relationship) in which a gain for one side entails a corresponding loss for the other side
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This is easy to see if you try to find an instance where there are no losers and all participants are winners: an impossibility.
Step 1:
Google IPO at $85 (gain $85)
Trader "A" buy at $85 (lose $85)
Step 2:
Google rise to $100
"A" sells at $100 (gain $100)
"B" buys at $100 (lose $100)
Step 3:
Google rise to $200
"B" sells at $200 (gain $200)
"C" buys at $200 (lose $200)
There will never be a step where a gain is not offset by a loss.
Count in commissions and its easy to see that this is a negative sum game.
Main Entry: zero-sum
Function: adjective
: of, relating to, or being a situation (as a game or relationship) in which a gain for one side entails a corresponding loss for the other side
------------------------------------------
This is easy to see if you try to find an instance where there are no losers and all participants are winners: an impossibility.
Step 1:
Google IPO at $85 (gain $85)
Trader "A" buy at $85 (lose $85)
Step 2:
Google rise to $100
"A" sells at $100 (gain $100)
"B" buys at $100 (lose $100)
Step 3:
Google rise to $200
"B" sells at $200 (gain $200)
"C" buys at $200 (lose $200)
There will never be a step where a gain is not offset by a loss.
Count in commissions and its easy to see that this is a negative sum game.