Philosophical puzzles

Philosophical puzzles, like the “Ship of Theseus” (see last blog), are much used in analytical philosophy and especially in the philosophy of action. Then I don’t mean logical puzzles or puzzles merely done for fun or for training your brain and, but puzzles with an ethical or practical aspect, so like Theseus’ Ship, which plays an important part in discussions on identity, or the trolley problem, which I used in my blog dated Feb. 18, 2013. They are good instruments for thinking through complicated issues. However, the reasonings involved rely on philosophical intuitions, and is it really true that such intuitions are the same for everybody, even if philosophically schooled? It’s doubtful. Therefore a new branch of philosophy has come into being, experimental philosophy, which investigates philosophical problems by presenting them to different groups of laymen, while using an experimental format (for instance using test groups with different cultural backgrounds).

Since my specialty is the philosophy of action, I am especially interested in puzzle cases in that field. Some are about what an action is, what intentionality is, and the like. Other ones try to distinguish actions “as such” and its side effects. Again other puzzle cases focus on the relation between action and causality. And maybe there are other categories as well. Donald Davidson, who left his mark on the development of modern action theory, uses several puzzle cases for examining the question if and under which conditions there is a causal relation between an agent’s beliefs and the result of an action by him or her. Such cases are of the type that someone wants to perform an action with an important consequence and the idea of doing so makes the agent so nervous that he loses the control of his body and just this makes that he does what he intended to do but not in the way or at the moment he wanted to do it. Here is an example by Davidson: “A climber might want to rid himself of the weight and danger of holding another man on a rope, and he might know that by loosening his hold on the rope he could rid himself of the weight and danger. This belief and want might so unnerve him as to cause him to loosen his hold, and yet it might be the case that he never chose to loosen his hold, nor did he do it intentionally.” (Davidson, 1980: 79). According to Davidson we can say only that the climber caused the fall of the co-climber if what the climber believed and wanted to do on the one hand and the fall of the co-climber on the other hand were causally related “in the right way”, and that is apparently not the case in this instance. Is he right? For one can also say that one needs to keep his nerves under control in such a situation, anyhow, since being unnerved can make that a climber loses control of what he does and he has to know that, and wrong beliefs can make a climber nervous. Maybe one must say that just because the climber’s belief and want were related in the wrong way to the fall of the co-climber they caused it. Isn’t it so that we are often held responsible for what we do, not as side effects but just as the thing we do, because what we intended to do is related in the wrong way to the consequences? Just this “being related in the wrong way” makes that we are often held responsible for what we didn’t believe and wanted to do and nevertheless actually did (in causing a traffic accident, for example).

These are only a few initial remarks about Davidson’s puzzle case. Much more space is necessary to flesh it out, and maybe finally I would draw another conclusion, if I did. But what all this shows is that a good puzzle case doesn’t only make you think (using your brain) but also gives you a lot to think about.

Reference: Donald Davidson¸ Essays on Actions and Events. Oxford: Clarendon Press, 1980.

Truth and the Ship of Theseus

Last week I mentioned the famous puzzle case of the Ship of Theseus. It was first put forward by the Ancient Greeks. Nowadays it is especially used in the debate on personal identity in the analytical philosophy. And indeed, the problem I discussed in my last blog has much to do with the question of group identity; in this case the identity of a group over time. But if a group like a sports team has a continuity over time despite changes in membership, just as the Ship of Theseus remains to exist when its planks are replaced one by one, does this mean that a group exists independent of the members who make up the group? The more I think about the case of the Ship of Theseus, the more intriguing questions come to my mind. It casts even doubt on one of the basic assumptions of classical logic, namely the law of excluded middle and double negation. The first part of this law says that for any proposition either it is true or its negation is true. The second part says that a statement cannot be true and not true at the same time.

To repeat, the case of the Ship of Theseus involves that the vessel is repaired by gradually taking out the old planks one by one and putting in new. Do we then still have the same ship at the end? Of course, Theseus, the owner of the ship who has commissioned the repair, will say “yes, we have”, and we’ll certainly agree if the old planks are destroyed. But suppose that someone has stolen the planks before they could be destroyed, builds a new ship with these planks (and only with these planks) and paints the name “Ship of Theseus” on it, just as on the original ship and on the one repaired by order of Theseus. Which ship is then the real Ship of Theseus? Say that just after the reparation has been finished, a fire completely destroys the ship with the new planks. Then the plank-hoarder appears and says: No problem, I have saved the ship for I have reconstructed the Ship of Theseus with the old planks. I think that it would be absurd to deny the truth of this claim. For if the Ship of Theseus would have been taken apart by taking away the planks one by one, storing the planks for a year, and then rebuilding the ship with the old planks, we would say the same. However, if we had replaced all old planks by new planks and would have destroyed the old planks, we would say that the ship with the new planks was the real Ship of Theseus. So whether the ship made of the old planks is the Ship of Theseus or whether the new ship is depends on the history of the building of the Ship of Theseus and on what has happened with the planks.

Suppose now that the repaired ship hasn’t caught fire and that the old planks haven’t been destroyed but used by an antique dealer to rebuild the Ship of Theseus. Theseus would say then, with right, that the old planks have been stolen and that the repaired ships is the real Ship of Theseus. But the antique dealer maintains that he wanted to save the original Ship of Theseus. Then he can also say with right that his ship is the real Ship of Theseus. As Noonan says about this case: “The identity statement in question is at worst indeterminate in truth-value” (p. 132). The problem can be solved by letting the truth of a proposition depend on who utters it (either Theseus or the antique dealer in my case), but classical logic does not allow this possibility: Either Theseus’ ship or the antique dealer’s ship is the real Ship of Theseus.

But suppose now that Theseus didn’t know that the old planks have not been destroyed and that they were used for rebuilding his original ship. Theseus puts out to sea with his repaired ship and he runs across the antique dealer with his ship. Theseus falls into a rage, when he sees another ship with the name “Ship of Theseus”, and he attacks it with his boat. We get a sea battle and one ship is destroyed and sinks. Then there are good reasons to call the winning ship the real Ship of Theseus, at least from then on. So the result of the battle determines which ship is the real Ship of Theseus. In other words, the truth of the proposition “The Ship of Theseus is identical with the ship constructed of the new planks” depends on the result of the battle. If Theseus wins it is true. However, this doesn’t involve that if the antique dealer wins this proposition is false. Moreover we have then the intriguing question, whether Theseus changes his opinion, in case he loses the battle. Maybe he considers from then on the ship rebuilt with the old planks again the real Ship of Theseus.

Source: Harold W. Noonan, Personal Identity. Second Edition. London: Routledge, 2003

A philosophical enigma

If we want to explain group behaviour, we are faced with the question: “What is a group?” Many answers have been given in philosophy, sociology and other disciplines. I’ll not try to evaluate them here. I want to consider a question that is relevant when we explain group actions from the perspective of analytical philosophy. Some examples of groups I am thinking of are people painting a house together, going for a walk together, a sports team, a task group, or a small company.

Although a group doesn’t have a shared intention, as we have seen in my last blog, usually it has a goal, which can be seen as the reason that brings the group members together, although it doesn’t need to be the intention that makes the group members act. It can make that people join the group.

Groups can be organised for only one task and once it has been executed, that’s it. Usually such groups are stable. Membership doesn’t change during the activity and once the task has been finished the group is dissolved. However, many groups have a longer duration: Its activity is permanent or at least it lasts quite a long time. Instances of such more or less permanent groups are sport teams and business companies. Then it often happens that members of the group have to be replaced now and then, temporarily or once and for all. Someone can become ill. Another member decides not to go on with the group. A member is replaced by someone who is more competent. And so on.

Let me take the case of the first team of a football club that wins the national cup. I call this team First Team (FT for short). Sometimes a team keeps the same core of players for years, but there are always changes from match to match and from year to year. Suppose that after fifteen years all players that once won the cup have left the team. Nevertheless it is normal to say “Finally, after fifteen years, the First Team has won the cup again”. One can say, of course, that in fact another team has won the cup and that it is not right to say that after fifteen years it was the First Team that has won the cup again, but then we have the problem to decide when the old guard (FTold) is no longer the new guard (FTnew) that wins the cup fifteen years later. Let’s say for simplicity that every year a player of FTold leaves the team and is replaced. So after eleven years FTold has become the FTnew that wins the cup again at last (I ignore the substitutes from match to match or even during a match). Then two views are possible. One is that FTnew is the same team as FTold, because it belongs to the same club, has a continuity in time with FTold, etc. The alternative view is that FTold and FTnew are different teams. But, as supposed, the change from FTold to FTnew is gradual, so when do we no longer have FTold and can we say that we have got FTnew instead? If one of the players of FTold leaves the team and is replaced, do we have then still the same team? If we say no, we have a problem, for everybody treats FTold still as the same First Team of our club. Moreover, say that the leaving player is injured and comes back after a few months, but after again a few months he leaves the team once and for all. Is it so then that we have two different teams during this period? Or is there a difference when a player leaves a team temporarily because of an injury and when he leaves it definitively? However, if we say that FTold remains the same after only one player has been replaced, then we can ask the same question, when a second player is replaced. If we say “yes” again, etc., then we have eleven new players that wins the cup after fifteen years and still we have the same team, although our view was that FTold and FTnew were different. Or must we say that we have a new team if at least half of the FTold players has been substituted? And why then just when six players have been substituted and not five or seven?

I can go on discussing this case and I can consider all kinds of variations. However, I think that the problem whether FTnew is or isn’t the same team as FTold has no solution. It is the same so for any other group in case members are replaced. I think that from one respect we can say that it’s still the same group and from another respect that a group with subsitutes is a new group, but the problem cannot be solved in a satisfactory way.

My case looks like the famous case of the Ship of Theseus – already discussed by the Ancient Greeks – which is repaired continuously by taking out old planks and putting in new. Do we still have at the end the same ship or do we have a new one? This problem of gradual substitution is one of the great enigmas of philosophy that until now nobody could solve and that maybe never will be solved. A group changes and nevertheless stays the same during the years. That’s all we can say about it.