the major similarity between the pennsylvania and the auburn system was:

The Auburn system was a penal method of the 19th century in which people worked during the day in small groups and were kept in solitary confinement at night, with absolute silence being enforced - with brutality, if needed - at all times. The Pennsylvania system was penal method based upon the idea that solitary confinement fostered penitence and encouraged reformation by inmates. The systems were much alike in that they both encouraged, silent, and often very brutal forms of punishment focused on solitary confinement.