  Modeling languages in software engineering (e.g., UML) evolved from software
systems modeling where denotational and operational kinds of semantics are the
traditional subjects of research and practice. According to some authors,
although a large portion of the static semantics (e.g., UML) seems to have
reached a consensus, the dynamic semantics of activities, interactions, and
state machines poses a major challenge. Central to semantics is the
relationship between a sentence and the (actual) world. Carefully examining
semantics-related issues in the modeling languages field to avoid problems that
may affect practical applicability is important. One effort in this direction
is OMG s release of a 2020 draft specification for Foundational UML (fUML),
with the base semantics specifying executions that are executable in the same
sense as a program in a traditional programming language. Additionally, efforts
within academia have sought to develop an alternative approach to modeling
languages using formal semantics (e.g., using Russell s theory of types and
Tarski s declarative semantics). This paper aims at a similar exploratory
venture of developing semantics, only for a much more modest diagrammatic
modeling language, called the thinging machine model. The model promotes a deep
understanding of the scrutinized modeling language and leads to considerably
fruitful questions. Constructing the thinging machine model seems to facilitate
progress in this direction, and the initial results in this paper indicate the
viability of the approach.
