For those with an interest in opinion as the ultimate foundation of political authority and legitimacy (including as an alternative to the social contract tradition) it is natural to focus on Hume’s writings, especially. But recently I noticed a chain of argument in Federalist 49 (presumably written by Madison) that, while Humean in character, also made a number of points that seemed to me to go beyond Hume’s views. Let me quote to get this digression rolling:
There is a lot going on in this passage. First, it matters to us to know what others think. While this is not Madison’s concern here, in ordinary life we need to know this in order to make our our own plans of action for our private ends. But also, if we want to pursue collective actions, knowing how others stand (or stand in our way) is crucial to success. How to coordinate on our collective plans, if any, in the context of uncertainty about others’ aspirations is crucial to many political contexts. Andy Sabl has written a lovely book on this very issue, Hume's Politics: Coordination and Crisis in the "History of England".
Second, on many issues if left to our own devices, we’re not really sure what to think. Society is complex and it is difficult to be an expert on everything. In societies like ours, in which the division of (cognitive) labor is advancing all the time, this problem is unsolvable. So, in areas outside our direct competence or familiarity, it is natural to look for cues on what to think in others. (Neil Levy has explored this in context of modern social epistemology, Bad Beliefs: why they happen to good people.) Madison assumes that we have a natural heuristic in topics of this sort that the strength of our belief varies with the number of people we see/perceive also having this belief.
As an aside, something like the natural heuristic still shapes democratic political life; perception of popularity is constantly manipulated and measured (opinion polls, think of bumper stickers, yard signs, memes, the controversy over Trump’s inaugural crowd, etc.). It may well also account for important outcomes that we observe in bandwagon effects in political voting (which otherwise seem rather odd, if not irrational).
In fact, Madison presupposes that even when we do have relatively firm views these are naturally going to be divergent. He says this explicitly shortly hereafter, in a paragraph in which he argues against regular national referenda or constitutional conventions. I quote:
Here Madison takes for granted that under settled governments there will be natural disagreement (“ordinary diversity of opinions”). He is explicit that in settled governments there will always be fierce opposition to it (that one may well think of as bordering on seditious): “passions most unfriendly to order and concord.” Given that Madison is not obscure in the education of the chattering classes, it is a bit odd how frequent public tumult in liberal democracies is occasion for surprise.
Not to put too fine point on it, but Madison has fully internalized Machiavelli’s idea that free societies are characterized by what one may call (recall) creative turbulence. Party attachments may dangerously strengthen these passions, while simultaneously be a way to make them conducive to public good.
It is only during revolutionary moments, when there is trust in leaders (who solve coordination problems), that this natural diversity of opinion disappears because there is a common enemy or a common set of grievances. For Madison the problem with regular national referenda/constitutional conventions is that one basically induces revolutionary moments without a glue that holds a people together.*
In writings on Madison (and Federalist 10), one often gets the sense that he thought that faction is the source of danger that needs to be managed; Marxists will hasten to add that he means by that those that attack property, while liberals that he means by that religious fanatics. (These are compatible, of course.) There is, of course, a kernel of truth in this. But the reason why factions are dangerous is that our natural heuristic is de facto manipulated: in the presence of like-minded others we become firmer in our views (the echo-chamber, etc.)
So it is true that factions are a crucial mechanism by which the uncertainty of one’s own isolated views is partially removed, and our beliefs become fixated. But factions are a symptom of the underlying problem not its cause. The real problem is that we cannot avoid such fallible heuristics to navigate social life. We will always seek out others and join them from interest, or devotion, or fandom, or own uncertainty.
* In fact, he goes on to make a significant observation
We have seen that the tendency of republican governments is to an aggrandizement of the legislative at the expense of the other departments. The appeals to the people, therefore, would usually be made by the executive and judiciary departments.
Plebescite populism is the natural ally of presidents and emperors.
Interesting analysis. Federalist 49, in particular the passage asserting opinion as the foundation for political authority, is (relatively briefly) is discussed by Hannah Arendt in her "Truth and Politics," which is well worth reading (and rereading).
https://german.yale.edu/sites/default/files/arendt.truth_and_politicslying_in_politics.pdf