Below in bold is the C portion of Blue Book listing 12.02. As even a casual observer might note, there are very few objective means to prove that this listing is met. For this reason, testimony and record development are the keystones of proving a case under this listing. An objective standard, while drawing a bright line between those who qualify for benefits and those who don't does not seem advisable in dealing with such uncertainty.
"12.02 C. Medically documented history of a chronic organic mental disorder of at least 2 years' duration that has caused more than a minimal limitation of ability to do basic work activities, with symptoms or signs currently attenuated by medication or psychosocial support, and one of the following:
1. Repeated episodes of decompensation, each of extended duration; or
2. A residual disease process that has resulted in such marginal adjustment that even a minimal increase in mental demands or change in the environment would be predicted to cause the individual to decompensate; or
3. Current history of 1 or more years' inability to function outside a highly supportive living arrangement, with an indication of continued need for such an arrangement."