\contentsline {section}{\numberline {1}Plan}{1}
\contentsline {subsection}{\numberline {1.1}Title}{1}
\contentsline {subsection}{\numberline {1.2}Structure}{1}
\contentsline {subsection}{\numberline {1.3}What the paper is about}{1}
\contentsline {subsection}{\numberline {1.4}What the paper is NOT about}{1}
\contentsline {subsubsection}{\numberline {1.4.1}On purpose}{1}
\contentsline {subsubsection}{\numberline {1.4.2}Due to lack of space}{2}
\contentsline {subsection}{\numberline {1.5}Admissibility condition}{2}
\contentsline {section}{\numberline {2}Matter}{3}
\contentsline {section}{\numberline {3}Modeling Partial Functions with Total Structures}{7}
\contentsline {section}{\numberline {4}Basic Notions for \relax $\Sigmaoffont $-Structures}{10}
\contentsline {section}{\numberline {5}Four Notions of Validity}{11}
\contentsline {section}{\numberline {6}Data Universes}{13}
\contentsline {subsection}{\numberline {6.1}Visible Sorts and Constructors}{13}
\contentsline {subsection}{\numberline {6.2}Hidden Sorts and Destructors}{14}
\contentsline {section}{\numberline {7}Fulfilledness and Rewriting}{23}
\contentsline {section}{Notes}{25}