**Visualizing Principal Doctrine 6** This doctrine has some issues with translation, but in the end the meaning seems clear. The text which is generally reproduced today is that in the attached graphic: "To secure protection from men anything is a natural good by which you may be able to attain that end." I have retained that formulation in this graphic because I believe that this statement is accurate to the thrust of Epicurean philosophy.
As stated at Attalus.org and other authorities, the text from which translators work references kingship, and can be translated into English as
"In order to obtain security from other people, there was (always) the natural good of sovereignty and kingship, through which (someone) once could have accomplished this."
Apparently many authorities, including Usener and Bignone, believe that the explanation here is that the reference to kingship was just such a reference, made by someone in commenting on the text over the ages, which at some point crept into the text itself. This theory would be consistent with the statement made elsewhere in the Epicurean texts that "the wise man in an occasion, will serve even a king/monarch."
Be that as it may, the wider view that anything (and not just the assistance of kings) is a natural good when necessary to obtain safety from other men. This wider meaning without the reference to kingship is amply supportable by Epicurean philosophy. One such example in a text that survives intact is Torquatus' statement in On Ends:
"Yet nevertheless some men indulge without limit their avarice, ambition and love of power, lust, gluttony and those other desires, which ill-gotten gains can never diminish but rather must inflame the more; inasmuch that they appear proper subjects for restraint rather than for reformation."
The same view is also consistent with the last of the Principal Doctrines, PD40:
As many as possess the power to procure complete immunity from their neighbors, these also live most pleasantly with one another, since they have the most certain pledge of security, and after they have enjoyed the fullest intimacy, they do not lament the previous departure of a dead friend, as though he were to be pitied.
So whether the subject is kingship or any other defensive or preventatively offensive device, the wider meaning is clear:
"To secure protection from men anything is a natural good by which you may be able to attain that end."
More graphics for Principal Doctrine 6 can be found here.