Some philosophical questions are so difficult you could tie yourself up in mental knots trying to understand them. But they do make great dinner party conversations.
These types of philosophical questions are usually known as thought experiments. People have been using these conundrums to understand philosophical concepts for nearly 2,000 years.
The purpose of a thought experiment is to explore the potential consequences of a certain principle. It is usually not possible, for physical or ethical reasons, to actually perform the experiment so a definitive answer can never be reached.
Here are 5 of the most mind-bending philosophical questions around.
1. Hotel Infinity
The Hotel Infinity paradox is used to explain the concept of infinity.
Picture a hotel in your mind. Try to imagine that this room has an infinite number of rooms with an infinite number of guests staying in them. Now, imagine you walked up to the reception and asked for a room. Unfortunately, the infinite rooms are full of infinite guests, meaning there is no room at the inn for you.
Luckily, the desk manager has a brainwave. He says: “I’ve got it. I’ll just move the guest in Room 1 to Room 2!” And he does. He moves the guest that was in Room 2 to Room 3, and Room 3 to Room 4, and so on—an infinite number of guests getting bumped deeper into the infinite number of rooms.
This seems perfectly reasonable. However, the hotel originally had an infinite number of guests and now it has infinity plus one. So which number is really infinity?
2. Beetle in a Box
Ludwig Wittgenstein (1889 –1951) was an Austrian-British philosopher. He published his book Philosophical Investigations in 1953, and it has since come to be recognized as one of the most important works of philosophy in the twentieth century. Wittgenstein was also the author of the famous beetle in the box thought experiment.
For this thought experiment, Wittgenstein asks that we imagine a group of people who each have a box containing something called a “beetle”. No one can see into anyone else’s box. Everyone is asked to describe their beetle, but each person can only talk about their own beetle, as there might be different things in each person’s box. Over time, the word “beetle” simply comes to mean “that thing that is in a person’s box.”
The mental experiment makes us think about how we describe our unique experiences. The beetle is like our minds. We can never know exactly what other people are experiencing. So, if someone says they are experiencing pain or love, we can never really know what that experience is like for them and whether it is the same for us.
3. The Trolley Problem
One of the most well-known ethical thought experiments is the Trolley Problem. This experiment was recently used to dramatic effect in the TV series The Good Place.
The experiment goes like this:
Imagine you are driving a trolley and the brakes fail. Up ahead are five people tied to the trolley tracks. You can choose to switch your trolley to another track. However, this track has one person tied to it.
You are now in a moral dilemma. If you do nothing, five people will die. However, if you take action to save those five people, your deed will lead to the death of an innocent person. This could be one of the hardest philosophical questions to answer.
4. The Experience Machine
The Experience Machine is a thought experiment put forward by philosopher Robert Nozick in his 1974 book Anarchy, State, and Utopia.
Suppose there was an experience machine that would give you any experience you desired. You can choose whatever experiences you want to have by pre-programming the machine. Once in the machine, your brain would be stimulated so that it felt like you were experiencing everything you had programmed. You would not know that these experiences weren’t real. For you, they would seem just like ordinary life. Plugging into the machine would eliminate toil, struggle and suffering and create a life of perfection. Would you plug in?
Many people would choose not to because this perfect life would not be ‘real’. But what would the difference be?
5. The Ship of Theseus
One of the oldest of all thought experiments is the paradox known as the Ship of Theseus, which originated in the writings of Plutarch.
In this philosophical question, you are asked to imagine a ship that has remained seaworthy for hundreds of years due to constant repairs.
As soon as one plank became old and rotted, it would be replaced, and so on until every working part of the ship was no longer original. The question is whether this ship is still the same Ship of Theseus, or something completely different. If it’s not the same ship, at what point did it become something new?
You could say the same for a person as each of our cells regenerates to the point that nothing left of the person we were when we were born remains. Does this mean we are a totally different person? If not, what is it that makes us the same person throughout our lives?
At its heart, the experiment forces one to question the commonly held idea that identity is solely contained in physical objects and phenomena.
Considering these philosophical questions might give you a bit of a headache. However, they do uncover some interesting moral and ethical issues. They also make us think about the nature of reality, life and who we really are!