APPEAL TO MODERATION
Ad Temperentiam [1]

1. Appeal to Moderation vs. Appeal to Radicalism

In politics, moderation is opposed to radicalism or extremism, just as reformism is opposed to revolution. Arguments from moderation emphasize stickin to the practical, compromising, taking inclusive positions, and changing things little by little.
The appeal to radicalism emphasizes the urgency of decisions, the need for new beginnings, avoiding dead ends in discussions. It also emphasizes the will to remain faithful to principles that can be framed as antinomies, “freedom or death”.

gTwo opposing ethos and emotional states are associated with moderation and radicalism: respectively conservative vs. progressive; open to dialogue and compromise vs. uncompromising; realist vs. idealist; serenity vs. exaltation; etc.

2. The Middle Ground Argument

The middle-ground argument justifies an action by showing that it does not satisfy any of the opposing parties. The speaker takes the position of the responsible third party, see roles.

Stay away from extremes.

The fact that both the far right and the far left are attacking my policy clearly shows that it is a good policy.

Christianity has restored true proportions in architecture, as in other arts . Our temples, larger than those of Athens, and smaller than those of Memphis–the right balance, where beauty and taste par excellence prevail.
Chateaubriand, [The Genius of Christianity], 1802[1]

The intermediate position is valued. Reason and virtue “stand in the middle” (Lat. in medio stat virtus):

Neither rash nor cowardly, but courageous.

However, an arguer who chooses the middle ground risks being stigmatized as indecisive, or unwilling to examine the arguments of the parties in detail: “let’s stop the discussion, meet in the middle and split the difference”.
The case of Solomon’s judgment shows that some issues that cannot be so easily divided.

[1] Latin. argument ad temperentiam, lat. temperentia, “moderation, measure, restraint”
[2] Quoted from François René de Châteaubriand, Le Génie du christianisme. Part 3, Book 1, Chapter 6. Tours: Mame, 1877, p. 194-195.