The Urist Rorschach Mutuality of Autonomy Scale (MAS), which assesses development along a self‐object differentiation and mutuality dimension, has shown considerable promise as an index of interpersonal relationship capacities. As such, MAS scores were predicted to correlate significantly with three measures of psychological pathology/health. The reliability of the scale was investigated with non‐S Rorschachs and found to be satisfactory. Four‐card Rorschachs from 60 previously hospitalized adults comprised the data source for the hypothesis test. Results suggest that the Mutuality Scale accurately reflects observed pathology severity at time of hospitalization and over a lifetime, but not at the time of assessment. Hence, the Urist MAS may indicate potential for pathology.