In Defensor Pacis in 1328 Marsilius noted:
The fruits of peace or tranquillity, then, are the greatest goods, as we have said, while those of its opposite, strife, are unbearable evils. Hence we ought to wish for peace, to seek it if we do not already have it, to conserve it once it is attained, and to repel with all our strength the strife which is opposed to it. To this end individual brethren, and in even greater degree groups and communities, are obliged to help one another, both from the feeling of heavenly love and from the bond or law of human society. This admonition Plato also gives us, as Tully attests in the first book of his treatise On Duties, when he said: “We were not born for ourselves alone; to part of us our native land lays claim, and to part, our friends.” To this sentence Tully adds: “And so, as the Stoics were wont to say, the things that grow in the earth are all created for the use of men; but men are born for the sake of men. In this we ought to follow the lead of nature, and to bring forth common utilities for all.” 11 But it would be no small common utility, indeed it is rather a necessity, to unmask the sophism of this singular cause of wars which threatens no small harm to all states and communities. Hence, whoever is willing and able to discern the common utility is obliged to give this matter his vigilant care and diligent efforts. For while this sophism remains concealed, this pestilence can in no way be avoided, nor its pernicious effect be completely uprooted from states or cities.
Peace is not just with respect to external threats but just as well to internal. Marsilus is credited with the articulation of the principle of the individual, as the fundamental element of the state, not as a subject of the state. For Marsilius the individual was every human, all with equal rights and all having a say for the selection of those who lead, once selected, then agreed to. Internal threats were also key to Marsilius since he was observant of the wars withing the Italian city states, the internal savagery of families and groups destroying the fundamental essence of individual freedom.
Just a thought for a few.