Democracy is one of the mechanisms that has made it possible for humans to build a global civilization that transcends our biological limitations, while still granting each and every one of us a large degree of freedom and safety, and the chance to pursue our dreams and find happiness in our own way. Unfortunately, not all of the world has this luxury, and even where we have it, there are threats to it. So let’s take a look at how it works, and why it’s important.

Direct and representative democracy

This post will mostly focus on the most common form of democracy, the representative democracy. It’s a system where the people don’t vote directly on political issues, but instead get to choose some reasonably competent politicians to represent them. These representatives are then allowed to make decisions on behalf of the people that elected them.

In contrast, direct democracy is a system where the people get to vote on political issues themselves. This is a less used system, in part because it’s difficult to get right, difficult to keep fair (especially to minority groups), and the decision-makers don’t need to be competent. Such concerns are why, for example, the founders of the United States of America did not want direct democracy. (However, there is a “middle road” in the form of semi-direct democracy, which is used in Switzerland.)

A comparison with machine learning

An interesting ways to look at how representative democracy works, is comparing it with machine learning methods known as ensemble learning. These methods are basically about building a collection of independent classifiers (algorithms and models that try to predict the correct classification of input data). By aggregating the predictions from all these classifiers in some way, you can create a classifier that’s correct more often than any of the individual classifers. For example, it’s possible to take a bunch of classifiers that’s correct only 51% of the time each, and combine them to create a classifier that’s correct 99.9% of the time. But ensemble methods are supervised learning methods, meaning the classifiers must receive feedback (usually in the form of training data) on whether its predictions were correct.

When comparing this to politics, we can see some interesting parallels. In a representative democracy, we can see politicians as classifiers, but we can also see voters as classifiers. Let’s take a look at each case, and what the implications are.

Politicians as classifiers

If each politician (or each political party) is like a classifier, then, even if each politician is correct only about half the time, it would still be possible to create a system where the decisions they collectively make are correct much more often than that. But to ensure that, we need a feedback system, ideally one that’s independent and unbiased.

In a representative democracy, the most important mechanism for this is the election. When people get to vote for who they think does the right thing most of the time, they thus provide feedback that allows both individual politicians, and the system as a whole, to make better decisions in the future.

There’s another lesson here: in general, an ensemble learning system works best when the individual classifiers are as diverse and independent as possible. This suggests that, for a representative democratic system to make as many good decisions as possible, its elected politicians should have as many different perspectives as possible (e.g., by having many political parties).

Voters as classifiers

Since this important feedback comes from voters, it’s also important that voters vote wisely, in some sense. Ideally, they would vote for whichever politician would objectively do the most good for them (the voters, not the politicians), but that’s not something voters necessarily know for sure, and politicians tend to be smooth talkers. So voters can only vote based on the facts they’re aware of. Fortunately, even if each voter only vote wisely about half the time, it’s still possible to have a system where the election result is beneficial much more often than that, but this needs a few things.

In democracies, each vote has the same weight. This is similar to an ensemble learning method known as “bagging”. The good news is that this method works even if each classifier doesn’t have access to all the data (much like real-life voters). The bad news is that it’s not guaranteed to work unless each classifier ends up as, on average, correct more than 50% of the time (though there’s some leeway when there are more than two result classes/candidates/parties). If the collective correctness gets too low, the system fails spectacularly (instead of getting 99.9% correctness, you may suddenly get more like 0.01% correctness).

That is, the system has a breaking point (and the fewer political parties you have, the smaller the leeway and higher the risk). To avoid it, voters have to be given the facts they need to make wise decisions. Fortunately, this important responsibility is generally handled by the free press.

Maintaining the system

Democracy can be a great system for ensuring good governance, even though neither politicians nor voters are perfect. But as we’ve seen, it’s possible for the system to break (even before we’ve considered politicians who abuse their power). To maintain a healthy democracy, we thus need things like:

• A democratic framework (voting system, etc) that corrupt politicians can’t easily change. Usually, the rules for democracies are written down into a constitution.
• An independent justice system. It must be able to enforce this constitution, and stand up to power-hungry politicians.
• An independent voting system. It must always be possible to remove misbehaving politicians.
• Voter choice. A one-party state is not a democracy, and a two-party state is a dysfunctional democracy. In a healthy democracy, voters should have a (realistic) choice of at least three political parties, and the voting rules should not discourage this. (When voting for individual candidates, this can be facilitated with ranked voting, for example.)
• Free speech. It must not be possible for politicians to put you in jail for criticizing them.
• Freedom of the press. It must not be possible for politicians and supporters to prevent the press from investigating and criticizing them. The press has a very important role in bringing facts to voters. (Unfortunately, not all media is unbiased and committed to facts, which can be a problem. But in a healthy democracy (one which has more than two political parties), the damage partisan media could cause would be limited and would not break the system.)
• No voter suppression. Everyone should be able to vote, and their vote should matter, regardless of gender, ethnicity, employment, or whatever. (In my personal opinion, even teenagers should be allowed to vote — after all, it’s they who have to suffer the consequences of our bad school policies and failing anti-bullying initiatives.)
• Codes of conduct. It must not be possible for politicians and supporters to suppress voices and facts through harassing people (but civil discourse must be possible).
• Literacy and education. If a majority of voters don’t understand the system and what/who they’re voting for, the system fails.

(It follows that, for example, the United States have been a dysfunctional democracy for a very long time, which partially explains some of the things that have been going on there lately.)

What we all can do

So, if we want to keep living in a healthy democracy, there are some things we can do (besides voting). The last two points in the list above are things we can all contribute to.

• Don’t tolerate harassment. Whenever someone engages in unwarranted personal attacks or makes threats because of differences in opinion (or gender or ethnicity or whatever), know that this is anti-democratic behavior and speak up, or report the person.
• Be a voice for truth. There’s a lot of misinformation out there, and democracy only works when people know the facts. Educate them when necessary.
• Whatever your beliefs, be a force for good! The point of democracy is to work together to create a better world for all of us. The point is not to hate or destroy each other. Be compassionate and tolerant, and do your best to make good things happen.