The Discovery of Trajectory Equifinality ModelD
Tatsuya Sato (Faculty of letters, Ritsumeikan University), Yuko Yasuda(Faculty of Education, Kyoto University), Ayae Kido (Faculty of letters, Ritsumeikan University), Saori Takada (School of Law, Ritsumeikan University) and Jaan Valsiner (Clark University)
Qualitative Research in Psychology, 5, 255-275,2006D
Abstract
@Qualitative psychology and cultural psychology are new beginnings
for the discipline of psychology. These new beginnings also require
a new methodology to fit the open systemic nature of phenomena.
The trajectory equifinality model (TEM) is a new methodology for
depicting the diversity of the course of human life. The concept
of equifinality originated in the general system model of von
Bertalanffy, and it means that the same final state may be reached
from different initial conditions and in different ways. It is
a general property of open systems. In the minimal case, the dynamics
of the open systems entail the notion of individual trajectories
that may diverge (at bifurcation points) or converge (at equifinality
points). Therefore, the TEM maps the individual histories of particular
systems onto the wider general system of possible trajectories
that arrive at the equifinality point. After reviewing the historical
and philosophical background of the TEM, important concepts such
as the equifinality point (EFP), trajectory, bifurcation point,
irreversible time, polarized EFP, and obligatory passage point
(OPP) are explained. Then, three studies applying this methodology
are presented so that new researchers can understand and practice
this new methodology. Finally, the implications and limitations
of the TEM are discussed. It is noted that all psychological research
necessarily needs to analyze processes of psychological kind (rather
than time-free essences that psychologists posit to "exist",
like "intelligence", "personality" etc.),
and TEM is a first step towards providing a workable alternative
to existing statistical orthodoxy.
Keywords
Trajectory equifinality model (TEM), qualitative psychology, equifinality
point (EFP), trajectory, system theory
The prototype of the TEM is here.
