Re "blood type" as a determinant of "personality:" As much as many, if not more than most, of the few.
 
Important to recognize is that "a blood type" represents a general biochemical mix, a sort of metabolic "mess of pottage." Nutrition via circulation in the human body affects much -- not the least of which is the shifting metabolic balance that people sometimes attempt to gauge through studies of cycles and patterns, be those patterns perceived as an individual's or a group's archetypal/creative processes, diurnal/circadian rhythms, seasonal sensibilities/disorders, or cosmogonic expressions/cosmological precessions.
 
Over macro-historical periods of elapsed calendar time, and perhaps more readily over natural historical periods, "blood type" may be used as a cipher or symbolic transform for an entire distribution of cultural/genetic personae. The matter of "cause" or "determination" remains an inferential, based either on high frequency/high intensity reinforcement of or on stochastic distributions from proven (survivable) patterns of species conduct as such express through an average or a cross-section of individuals, respectively.
 
It is not only possible theoretically but practically plausible that some single "individual" may come to "embody" most if not all of these causal/determinant characteristics for a definable population. The more such is the case, the more likely that the correlation between "blood type" and personality will be high. As detailed work progresses on the human genome project, and applications emerge based on the resulting new sciences during the coming century or so, it may become probable that the gap between changes incurred through reinforcement, on the one side, and stability evinced through survival of conflict, on the other side, will narrow significantly. In other words, premeditation of inference will equivocate with immediacy of reference. This sort of "equivalence"  could allow us to formulate. or perhaps even to calculate, affect and effect when it comes to blood type and personality. At such a point, "cause" and "determinant" will have been reduced to less than speculative, technical issues.
 
In the past thirty years, some USA and European empirical observers have even begun to develop socionomic/matic models for individual conduct and testable theories of cultural creation for collective experience. As these models and theories grow deeper roots in multicultural perspectives and become more consensual and reliable, they will likely provide a viable -- perhaps the only  -- strategic framework to guide alignment for and benefit from our necessary innovation and renovation of the human prospect.
 
Questions as to the substance or content of personality and culture are equally likely to become ever more important with respect to the formation of psychic identities and social characters.
 
THESE COMMENTS ARE FORWARD-FACING IN CERTAIN RESPECTS. NO CLAIM IS MADE TO THE FINAL TRUTH OR VALUE OF ANY ONE OF THEM. THE IDEAL READER IS ADVISED TO REGARD THEM SKEPTICALLY.
 
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