To be able to “classify” or say something about another human being, or himself for that matter!, personal qualities and destiny, etc. Astrology, graphology, chiomanti, frenology, coffee grounds… Similarities and differences? “Science”? What are you thinking?
First of all, graphology stands out from the other “-ogies”, as I see it. The others (incl. tarot, i-ching, etc) I think – if anything – can serve as a medium for the interpreter’s own wisdom and psychological insight, human knowledge, life experience… A form of cold reading.
But this to have a larger system that you submit to, trust, I think can further foster and stimulate one’s openness, positive seriousness, sense of responsibility, etc. That is, a positive thing.
But, that actually there is not so much to “touch” in the tarot cards or planetary constellations, which says something specific about the person you have in front of you. More than that the accumulated knowledge accumulated over the millennia around, for example, astrology or i-ching gives a very deep undifferentiated picture of man.
Yes, there were some quick thoughts. (But, i.e., graphology I want to place in a middle ground, it is more “science” than the others.)