Grossman-Stiglitz Paradox
The Grossman–Stiglitz Paradox is a paradox introduced by Sanford J. Grossman and Joseph Stiglitz in a joint publication in American Economic Review in 1980 that argues perfectly informationally efficient markets are an impossibility since, if prices perfectly reflected available information, there is no profit to gathering information, in which case there would be little reason to trade and markets would eventually c
Metadata
- Slug: 00176-grossman-stiglitz-paradox
- Type: PARADOX
- Tags: economics
- Sources: 1
Axioms
- Assume the rules of the domain apply uniformly.
- Assume the observer’s criteria remain fixed.
- Assume classification boundaries stay consistent.
- Assume the model describes the real case.
- Assume repeated steps do not change the outcome.
- Assume no hidden variables are introduced midstream.
Contradictions
- Two reasonable lines of inference yield opposite conclusions
- A global rule conflicts with a local judgment
- A stable resolution appears to violate a starting premise
- Changing the framing reverses the outcome
- Intuition and formalism diverge at the same step
Prompts
- Which assumption is doing the most hidden work?
- What changes if you relax the smallest constraint?
- Does the paradox dissolve or relocate when reframed?
- What is conserved, and what is sacrificed?
Notes
Sources
Overview
The Grossman–Stiglitz Paradox is a paradox introduced by Sanford J. Grossman and Joseph Stiglitz in a joint publication in American Economic Review in 1980 that argues perfectly informationally efficient markets are an impossibility since, if prices perfectly reflected available information, there is no profit to gathering information, in which case there would be little reason to trade and markets would eventually c
Tension
- Two reasonable lines of inference yield opposite conclusions.
- A global rule conflicts with a local judgment.
- A stable resolution appears to violate a starting premise.
- Changing the framing reverses the outcome.
- Intuition and formalism diverge at the same step.
Why It Matters
This entry tests how a stable rule-set can yield unstable conclusions under certain assumptions.
Prompts
- Which assumption is doing the most hidden work?
- What changes if you relax the smallest constraint?
- Does the paradox dissolve or relocate when reframed?
- What is conserved, and what is sacrificed?