Hopefully at least some people found the first article interesting. I think thought experiments are fascinating (the ones that aren’t too confusing, anyway), and so  wrote a part 2. For those who missed part 1, here is my definition of a thought experiment:

Simply put it is an experiment which takes place in your mind instead of in a laboratory. They are usually used to illustrate a point, or as an alternative when an actual physical experiment would be impossible or inhumane (such as Schroedinger’s cat).

The Ship Of Theseus – There is a ship that has been sailing for hundreds of years, thanks to constant repairs and replacement parts. In fact, it has been sailing for so long and repaired so often that there are no longer any original pieces on the vessel. So the question is whether the ship is still the same as the original, even though there are no original pieces and, if not, when did it stop being the original ship? This thought experiment is to explore how you feel about identity. What makes a person, a person?

An updated version of this is that a band changes members over several years so that no original members remain. Is the band still the same band?

My Take: Yes. Same ship, same band. For me identity isn’t just about the physical parts, it’s about feelings and other less substantial things. Identity isn’t just about the relationship about parts to the whole, but also about the connections between the whole and outside influences.

Brain In A Vat – A mad scientist has removed your brain from your body (let’s pretend that he somehow did it without your knowledge). He has placed it in a vat with electrodes attached. The mad scientist is now able to simulate all of your daily experiences. Since everything is processed through your brain, how could you ever prove that the world around you isn’t real? For that matter, how can you prove now that the world around you is real and not just a simulation?

My Take: I don’t have any good answer for figuring out what is real and what might be simulated, but in the end it doesn’t really matter. Even if you were just a brain in a vat, what could you do? You can’t unplug yourself and, as long as you aren’t being tortured or something, I would imagine that fake memories are better than being dead.

Survival Lottery – Imagine you live in a world where organ transplantation was perfect. There is no rejection of the organ and people who receive the transplant are cured. In this experiment you are asked to assume the following: the person donating the organs will always die, there is no difference between killing a person and letting someone die, and you can always save two people for every one person who donates. The experiment states that given these circumstances, it would be better to adopt a lottery where one person is randomly chosen every so often to donate their organs whether they like it or not.

My Take: The argument to this experiment is that you can not be assured that two lives are necessarily of more value than the one sacrificed. While I would normally say that it would be okay to sacrifice one for the greater good of saving two, in this case there is no guarantee that saving two is the greater good. Since the lottery is completely random, you could be condemning a great humanitarian or leader to save the life of a murderer or torturer. While I believe that every life has value, the question seems to be does every life have the same value?

What do you think? How would you decide?