  A general theory based upon 6 postulates is introduced. The basical notions
are theoretical variables that are associated with an observer or with a group
of communicating observers. These variables may be accessible or inaccessible.
From these postulates, the ordinary formalism of quantum theory is derived. The
mathematical derivations are not given in this article, but I refer to the
recent articles [9, 10]. Three possible applications of the general theory can
be given; 1) The variables may decision variables connected to the decisions of
a person or of a group of persons. 2) The variables may be statistical
parameters or future data, But most importantly here: 3) The variables are
physical variables in some context. This last application gives a completely
new foundation of quantum mechanics, a foundation which in my opinion is much
more easy to understand than the ordinary formalism.The other applications seem
also to give interesting consequences of the approach. Socalled paradoxes like
that of Schr\"odinger's cat can be clarified under the theory. Explanations of
the outcomes of David Bohm's version of the EPR experiment and of the Bell
experiment are provided. Finally, references to links towards relativity theory
and to quantum field theory are given. The concluding remarks point at further
possible developments.
