In keeping with his predilection for intertwining nature and figurative language, Paine utilizes an extended metaphor throughout the first section, comparing power to a disease and the monarchy to its host:
To say that the commons is a check upon the king, presupposes two things:
First — That the king is not to be trusted without being looked after, or in other words, that a thirst for absolute power is the natural disease of the monarchy.
In the above excerpt, Paine likens government corruption and the thirst for "absolute power" to a physical disease or illness. The moral condemnation goes both ways with this comparison—it was not uncommon in the 18th century for people to view disease as the natural consequence of a person's immoral character. This metaphor also functions to link the physical body with the "body politic," thereby connecting biology and body with the nation.
In an earlier passage, Paine further extends this metaphor, stating that
The constitution of England is so exceedingly complex, that the nation may suffer for years together without being able to discover in which part the fault lies, some will say in one and some in another, and every political physician will advise a different medicine.
If power and corruption are the diseases that must be cured in this metaphor, politicians take on the role of physician. Paine does not seem to view these politician-physicians as competent, however: they are as flawed as the system itself, pointing out faults where there are none and ignoring manifestations of the disease in other locales. The solution, then, cannot be to simply cure the disease; one must upend and recreate the entire system.
