---
tag: HBW4953ZV2
kind: concept
name: Cichoń's diagram
aliases: [cichon-diagram]
sources:
  - wikipedia: en:5709055@r1331217142
    locator: Cichoń's diagram
    note: adopted
    mention: wikipedia://en/5709055
    sections: [Summary]
same_as:
  wikidata: Q5119413
  wikipedia: Cichoń's diagram
inventory: [FYE1FENZ3B]
---

## Summary

In set theory, **Cichoń's diagram** or **Cichon's diagram** is a table of 10 infinite [[cardinal numbers|0EBACQFAZW]] related to the set theory of the reals displaying the provable relations between these cardinal characteristics of the continuum. All these cardinals are greater than or equal to $\aleph_1$, the smallest uncountable cardinal, and they are bounded above by $2^{\aleph_0}$, the [[cardinality of the continuum|0WC28W9DNM]]. Four cardinals describe properties of the ideal of sets of measure zero; four more describe the corresponding properties of the ideal of [[meager sets (first category sets)|0FQPYAY9PJ]].