In a number of progressive sciences, a single unifying theory, helping to explain numerous research problems within the frameworks of those sciences, exists. The field of developmental psychology is not unified by a single overarching theory which can be seen in a variety of complex explanations behind different phenomena in it.
The absence of a single line of reasoning shows that a single theory in developmental psychology does not exist. To illustrate this, the example of physics may be analyzed. There exists the doctrine of relativity in physics which explains a lot of physical phenomena in the Universe, and helps scientists in achieving considerable progress in their researches. However, there are no such theories in psychology.
Still, a unified theory in psychology including its every area such as developmental psychology or social psychology is very important. The absence of this theory makes the work of scientists complicated because they have to explain a variety of psychological phenomena without a single approach.
In case, a unified theory in psychology is developed, considerable progress in this scientific area will occur. Again, the illustration of physics may be addressed. When Einstein formulated his doctrine of relativity, many physicists managed to make outstanding findings and invent different mechanisms boggling people’s minds. Due to Einstein’s doctrine of relativity, Soviet scientists were able to produce a space rocket. It is very likely that a unified theory in psychology will help having outstanding revelations in the area of psychological research.
In conclusion, there exists no unified theory in psychology today. Still, the consequences of possible invention of such theory can be hardly underestimated by the specialists as they will by all means lead to a considerable progress.
References
Henriques, G. (2012). Why a Unified Theory of Psychology Is Impossible. Web.
Hunt, M. (2007). The story of psychology. New York, NY: Anchor Books.