Final answer:
The Pennsylvania Penitentiary believed the best hope for rehabilitating criminals lay in solitude, religious instruction, and hard work, in order to isolate them from societal vices and guide them towards moral reformation.
Step-by-step explanation:
The Pennsylvania Penitentiary operated on the principle that the best hope of rehabilitating the criminal spirit was through solitude, religious instruction, and hard labor. This approach aimed to isolate prisoners from the corrupting influences of society and encourage moral reformation. The penitentiary was structured to prevent communication among inmates, in the belief that solitary confinement would lead to repentance and reform. Alongside this, a regime of hard work was thought to instill discipline and industrious habits, while religious teachings would guide prisoners towards redemption and proper moral conduct.
This system further reflected a broader movement during the period which sought to transform social deviants by creating public institutions like penitentiaries, asylums, and workhouses. While debtor's prisons began to disappear, reflecting a shift in approach from punishment to reform, the rise of such institutions like the penitentiary embraced the philosophy that through appropriate intervention, those who have strayed could be redirected onto a righteous path. The idea of reforming rather than merely punishing criminals was a significant shift in the concept of incarceration and became a hallmark of the 19th-century penal reform movements in the United States.