These two theories have created debates between psychologists for many years. Hans j. Eysenck, Ph.D., D.Sc., is one of the world's most cited psychologists. He is a professor at the Institute of Psychiatry of the University of London, where he started the discipline of clinical psychology in Great Britain. He is a pioneer in the use of behavior therapy as well as research in personality theory and measurements.

The biological theory has to do with his findings that individual differences in personality are biology based. This was based on his theory that there are three dimensions of personality (super factors). These dimensions of personality were extraversion-introversion, neuroticism, and psychoticism. To check his work by using cross-cultural studies that produced much the same conclusion. Hans also went a step farther in pointing out the results of many studies indicating that genetics play an important role in deciding the amounts of which of the three personality dimensions one might possess. There are many pro's and con's to this theory but most psychologist will admit that it is getting increasingly harder to ignore the obvious link between our evolutionary history and our genetic makeup. There are some weaknesses to this theory. There is criticism that several of the ideas can't be tested in actual experiments. The psychologists are prone to use reasonable deduction in many instances, which may not give an accurate assessment. For example several types on direct manipulation would be illegal to perform which makes demonstrations of cause and effects difficult. There are other concerns over the research on temperament. There doesn't seem to be an agreement on the number of dimensions. In the EAS temperament model there are three dimensions identified, but there are several other models in use that describe additional dimensions. This creates a problem for psychologists and students alike in confirming which is the correct model. Lastly this theory offers us very little in the area of personality change.

In humanistic theory, the motivation for developing one's full learning potential is inherent in each of us. Although there is no real definition for the humanistic theory the four primary humanistic categories are personal responsibility, the here and now, the phenomenology of the individual, and personal growth.

This theory is unlike the biological theory in which we are creatures without control over our personalities in that it believes that all of us are born with the ability to shape our own futures and are limited only by our physical limitations. The here and now is just exactly what it sounds like. It reminds us that we should live for the present and not get caught up in the past. This has the tendency to limit what we may become and leave us short of our personal goals and or objectives. The Phenomenology of the individual deals with the concept that no one knows you as an individual better than you. It is ludicrous to think that some doctor could have any clue as to what to advise after only hearing your problem a few moments earlier. This could mean that we need to communicate our problems to someone from time to time, but one will eventually come to his or her own conclusion after careful reflection. The last category is Personal Growth. This process has to do with becoming a fully functioning individual achieving personal satisfaction. All of us strive to meet our immediate needs. This process states that once our immediate needs are met if left alone we continue to strive toward this ultimate satisfying state of being.

The problem with this theory is that much of it can't be tested in a scientific atmosphere. A large portion of this theory relies on the concept of free will. It isn't observable or predictable so how can it be testable. The other problem with this theory is that it is loosely defined terms like self-actualization and full functioning. Many researchers feel that we need more information on these terms before they can be clearly defined.

In conclusion I feel that both these theories possess credibility, but personally I think that I would take certain aspects from both theories to create something of a collage theory. I can't believe that we have no control over our personalities but at the same time I can see some genetic predisposition in our personalities.

References

Eysenck, H.J. (1995). Genius: The natural history of creativity. Cambridge, UK: Cambridge University Press.

Eysenck, H.J. (1997). Rebel with a cause: The autobiography of Hans Eysenck. (Revised and expanded edition.) New Brunswick, NJ: Transaction Publishers.

Guilford, J.P. (1967). The nature of human intelligence. New York: McGraw-Hill.

Hendrickson, A.E. (1982). The biological basis of intelligence, Part I: Theory. In H.J. Eysenck (Ed.), A model for intelligence (pp. 151-196). Berlin: Springer.