The inequalities among the ideals of measure (null sets) and category (meagre sets) are captured in Cichon's diagram. Seventeen models (forcing constructions) were produced during the 1980s, starting with work of Arnold Miller, to demonstrate that no other inequalities are provable.
The distinctions between measure ideals (null sets) and category ideals (meagre sets) are depicted in Cichon's diagram. In the 1980s, seventeen models (forcing constructions) were developed by Arnold Miller to prove that no other inequalities can be established.