This paper argues the expediency and need for a comprehensive design
methodology to be introduced not only to the context ofknowledge- based
CAAD, but also to the contexts of design philosophy and theory of
architectural Design. The ultimate purpose of the comprehensive design
methodology is to produce design descriptions as large systems rather than to
increase our understanding about how the design reasoning could be
accomplished in a harmonic and orchestralizational whole through different
levels of abstraction. Then , this study discusses such philosophic and
theoretical foundations about the ambiguity of absolute design truth and
relativity of design knowledge in order to recognize and extract the main
features of the design knowledge . Furthermore, this study controverts the
design theorization versus the design modelling aiming at looking for the most
convenient intellectual human activity by which the comprehensive design
methodology could be configured. Finally, An epistemological design
approach is proposed and discussed through a proposed group of theoretical
and philosophic hypotheses. Virtually, all the proposed philosophic and
theoretical hypotheses, this study introduces and considers, could be become a
subject of some contention. This is because, it is not possible to prove that they
are correct. Consequently, they are assumed to be correct or at least "
appropriate " enough for design context until they will be refuted by new future
empirical evidences, or superseded by more consistent profound ones. They are
just an admissible contribution to the design context.