For my one required college speech class, I did a speech on Graphology. A few years prior in high school, I did a speech on telekinesis. In my estimation, both are forms of divination.
According to the New Advent webpage, divination is: "The seeking after knowledge of future or hidden things by inadequate means. The means being inadequate they must, therefore, the supplemented by some power which is represented all through history as coming from gods or evil spirits. Hence the word divination has a sinister signification. As prophecy is the lawful knowledge of the future divination, its superstitious counterpart, is the unlawful. As magic aims to do, divination aims to know."
Involvement in divination will earn you a trip to confession.
My cousin, the sister, is a Graphologist. I'm not quite sure these things are compatable. Maybe graphology is an extension of a form of psychology, but it also has some fortune-telling aspects to it. I don't know if I think it is a tool that should be used to predict future behaviors, because while we may have natural tendencies and inclinations, we have the will to choose a very different course of action. God could give us the grace to overcome a vice or strengthen a virtue.
I once filled out a job application that asked me for a sample of my handwriting. I strongly suspected they were going to analyze my handwriting and refused. The job wasn't worth it to me. I've also had companies want me to take the MMPI and I refused that too. I've taken the MMPI a few times. The first time was in college because I had a psychology minor and really wanted to find out what this monster test was like. Having taken it, I really didn't want this type of information in the hands of my employer or have my answers assessed by some unknown person, with their own personal biases, who may or may not be qualified to interpret the results.
From the Wiki site:
Graphology is based upon the following basic assertions:
When we write, the ego is active but it is not always active to the same degree. Its activity waxes and wanes; being at its highest level when an effort has to be made by the writer and at its lowest level when the motion of the writing organ has gained momentum and is driven by it.
When the action of writing is comparatively difficult, the writer uses those forms of letters which are simpler or more familiar.
The muscular movements involved in writing are under the direct influence of the central nervous system. The form of the resultant writing movement is modified further by the flexibly assembled coordinative structures in the hand, arm, and shoulder; which follow the principles of dynamical systems. The specific writing organ (mouth, foot, hand,crook of elbow) is irrelevant if it functions normally and is sufficiently adapted to its function.
The neurophysiological mechanisms which contribute to the written movement are related to conditions within the central nervous system and vary in accordance with them. The written strokes, therefore, reflect both transitory and long term changes in the central nervous system such as Parkinson's disease, or alcohol usage.
The movements and corresponding levels of muscular tension in writing are mostly outside of conscious control and subject to the ideomotor effect. Emotion, mental state, and biomechanical factors such as muscle stiffness and elasticity are reflected in a person's handwriting.
One must examine the handwriting or drawing movements by considering them as movements organized by the central nervous system and produced under biomechanical and dynamical constraints. Given these considerations, graphologists proceed to evaluate the pattern, form, movement, rhythm, quality, and consistency of the graphic stroke in terms of psychological interpretations. Such interpretations vary according to the graphological theory applied by the analyst.
Most schools of thought in graphology concur that a single graphological element can be a component of many different clusters, with each cluster having a different psychological interpretation. The significance of the cluster can be assessed accurately by tracing each component of the cluster back to their origins and adapting the meaning of the latter to the conditions of the milieu in which the form appears.
I'm not a psychologist, but it seems that graphology is based on limited observations, personal interpretations (theories), and deals with the mind which is influenced by so many factors that you can't develop a test that controls for everything, with the goal being to test for one specific attribute. At best it's a snap-shot in time, at worst it's something Father will tell you to do penance for.