We all have that one friend who likes to do weird things out of seemingly nowhere. That, or they just say stuff with no filter. While we have a tendency to associate them with being “that random friend,” we know deep down that they’re probably not behaving 100% randomly. You might think your music player shuffles your music randomly–turns out that isn’t the case either. So what does “random” really mean? What is randomness?

**What Is Randomness?**

No, we don’t mean that weird “haha, I’m so random and quirky” meme energy. According to our good friend Merriam-Webster, “random” is simply something without definite aim, direction, rule, or method. Seems simple, right?

We’ll go back to the music shuffle shenanigans. Anyone can write a random number generator. So why do iTunes, Spotify, and other companies of that ilk produce messages like “we’re still working on our shuffle algorithm”? Yeah, no surprise, it’s not random at all. You can thank human psychology for that. Well, that and the fact that corporations want to maximize your time spent on their platform. Their algorithms are engineered to perfectly min-max the balance between you thinking things are random and keeping you listening.

Anyway, cynicism towards corporations aside, the human brain is also *really bad* at telling us what is and is not random. We *love *recognizing patterns, and we see them when there is no correlation. For example seeing faces in vague objects.

Way back when, iTunes used to be completely random, and then people started accusing Apple of making shuffle *not* random (even though it was basically just a random number generator) because they started recognizing patterns. So then Apple made things not at all random–but people were like “cool, things are actually random now.” Brains are weird.

**When Did We Come Up with Random?**

Well, you can obviously think of things that are truly random. A perfectly balanced die, for instance.

In the past, when humans were discovering all sorts of things, “randomness” and “fate” basically meant the same thing. In a simplified example, imagine a peasant farmer rolling a die and getting a six, and then taking that as a sign that a good harvest is coming six months from now. It is common for humans to take a random occurrence and apply some sort of greater meaning to it. When you don’t really know how anything works, taking two different things you can’t control and conflating them kind of makes sense.

Then all that transformed into gambling.

**Probability Is Weird**

Here’s something that will probably screw with your head. Knowing more information about a scenario changes the probability of something. There are a handful of names and scenarios for this, like the Boy or Girl paradox, but we’ll blaze through one called the Monty Hall problem.

*Monty Hall Problem*

*Monty Hall Problem*

Here’s the scenario, you’ve got 3 doors. Behind one door is a car, and behind the other two are goats. You pick door 1, and it is revealed that behind door 3 there is a goat. Now, you can choose between doors 1 and 2.

The question is therefore as follows, is it better to stay with door 1, or switch to door 2?

Logically you would argue that there is a 50% chance door 1 now has a car behind it, and a 50% chance door 2 has the goat. But it turns out, you should switch.

When you chose door 1, you knew that there was a 33% chance that you would win. If you stay, there remains the fact that you had a 33% chance to win. This means there is a 66% chance there is a goat behind your door. Knowing that behind door 3 there is a goat actually changes things quite a bit.

Because it’s more likely that you initially picked a goat, it’s more likely you win by switching from your initial decision.

*Marilyn vos Savant*

*Marilyn vos Savant*

Alright this is a bit of a tangent, but we think it’s worth pointing out. 1 because it’s funny, and 2 because Marilyn vos Savant solved the Monty Hall problem we just talked about. Also hey, we could all do with more discourse about women in science.

While IQ scores don’t mean all that much, she also held the highest one from 1986 to 1989. If you value that number, you can hold this information dear. If you don’t care about IQ scores, we’re moving on anyway.

Marilyn vos Savant wrote an article that was eventually featured in *The New York Times* in the 1990s about the Monty Hall problem, with the solution that we described above. Following, she received *many* letters (some 10,000) dedicated to telling her she was wrong.

Unfazed, Savant would release a *very in depth* discussion of the problem, breaking it down step by step. She would be accused of using “woman logic” afterwards.

Anyway, shout out to women in science.

*Why Discuss Probability?*

*Why Discuss Probability?*

Part of that discussion was to mess with your head, but we think it’s important to understand probability if you’re gonna understand randomness. Basically, as stated, randomness is the inability to know what the probability is. What we were trying to communicate is that probability can change depending on what information you do or do not have. Like with Monty Hall, having more knowledge of the situation not only changed your probability of success, but also kind of the probability that you would have succeeded earlier.

Basically, having information can make something that seems statistically random no longer random–making true randomness *even harder* to find.

**Where Can We Find Randomness?**

Luckily, there’s one super easy way to observe randomness. Just look outside and have a chat with Charles Darwin. The whole idea of natural selection *relies* on randomness.

Humans are the way they are mostly by accident. One day one of our ancestors was born with a larger brain compared to other primates. This big brain proved advantageous, and the trait was gradually passed to other generations. But it is also because of this randomness that weird evolutionary stuff exists. Kind of like how we all have an appendix, but we don’t like…need it at all. Many things fall into this “it didn’t kill you, so we guess it’s not bad” category.

*More Darwinian Posts: Why do Dogs Have Floppy Ears? | Did Dinosaurs Have Feathers?*

There’s also quantum physics. We’ve touched on it before on the blog, so you can do more of an in-depth look in the post below. But part of quantum mechanics is subatomic particles whose nature cannot be discerned until it is observed. Until it is observed, it is all possible states at once, and we have to treat it as such. Until we know which state it is, the particle’s condition is considered statistically and truly random.

*Further Reading: What are Quarks?*

*Fed up with randomness? Here’s a quiz you *cannot* take randomly.*