Diagrams of sphere models for variably strict conditionals (Lewis counterfactuals)
David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere semantics for counterfactual conditionals. He jokingly referred to the diagrams depicting such sphere models as Ptolemaic astronomy, hence the name of this package. The macros provided in this package aid in the construction of sphere model diagrams in the style of Lewis. The macros all make use of TikZ.
You can contact the maintainers of this package via email at
texlive dash maintainers at fedoraproject dot org.