Object-oriented programming has been around for more
than 50 years and is now the most dominant style of
programming. In recent years there has been an increasing
criticism of object-oriented programming. Some people
argue that the mainstream object-oriented languages do
not capture the intentions of object-orientation as intended
by its founding fathers. There are indeed issues with objectorientation
as practiced by mainstream. In this essay, we
identify a number of issues that we think are problematic.
We argue that the primary reason for these issues is that
reuse is considered the main advantage of objectorientation
at the expense of modeling. We argue that
modeling should be the main focus, that programming is
modeling, and we describe a number of principles to follow
when practicing object-oriented modeling.