Jointly Held Obligations

What does it mean to say that a number of agents jointly hold a moral obligation? On my view, collective obligations are not a novel type of obligation, but are moral obligations held in a col­lective mode: I can individually hold an obligation to do x or we (for instance you and I) can jointly hold an obligation to do x (for instance where x is only collectively feasible).

Joint obligations give rise to further individual obligations. If you and I jointly have an obligation to lift a heavy table, then each of us has an individual obligation to do our part or make an effort towards the joint endeavor. But joint obligations do not reduce to individual obligations to play our part. In order to see why, let us return to wide joint necessity cases, where we have more potential contributors then minimally necessary for the success of the collective performance. Suppose that it takes two people to lift a heavy table, but three poten­tial contributors are available. Suppose further, that two is also the maximum number of people who can successfully lift the table together, because of the way each needs to position them­selves to lift it. So out of the three potential contributors only two should act. It cannot be the case that each of the three has an obligation to act (since a three-way effort will not succeed). Neither should we think that any combination of two people (out of the three) is obligated to contribute. Because if we did, we would either (i) arrive at an impasse where we could not say exactly which two people have these obligations (that is, we would arrive at the following disjunctive obligation: Either a and b are obligated to do their part in lifting the table together, or b and c are so obligated, or a and c). Or, (ii) we would have to make an arbitrary decision on which two people have these obligations.

Instead, I suggest that the joint obligation is on all three and the individual (contributory) obligations will be derived from it. For instance, we may all be under an obligation to see to it that two of us lift the table together and one of us makes sure not to interfere. In order to do this, we will usually have to communicate with each other. This may be non-verbal communication. In everyday life, we often coordinate our actions this way — just think of a scenario where some passers-by rush to help someone who has trouble lifting a pram into a bus while others stay behind ready to step up if necessary.

But we need not always be able to communicate with each other in order to acquire (and discharge) a collective obligation. Sometimes having the right information concerning the other agents’ beliefs will suffice. Suppose that you and I live on opposite shores of a protected lake and in order to preserve the lake’s sensitive ecosystem and keep its pristine water clean we are instructed (by the local council) to ensure that no sewage or gray water enters the lake. We also learn that every neighbor is being thus instructed. Now I can do my part of not allowing any polluted water to enter the lake and so can you. But neither of us can guarantee that the lake’s water is not compromised. That outcome we can only produce together. Assuming that the pristine ecosystem is valuable and no overriding concerns exist, we are under an obligation to protect it. This obligation is held by both of us, jointly. It is not an obligation held by either of us, because neither can discharge it alone. Note that this does not require us to act together in the strict sense. Note also, that a joint plan is in place (via the local council’s communication), which ascribes to each of us a clearly circumscribed role in the collective effort (and which, furthermore, communicates that very fact to each of us).

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