People-Seeds
Tiny people-seeds drift through windows and take root in your carpet, developing into people. You've installed screens, but one gets through. Are you now obligated to let it develop?
Judith Jarvis Thomson invented this scenario in 1971 as a follow-up to the violinist argument. It addresses the specific case where pregnancy results not from reckless disregard but from precautions that failed, and tests whether the failure of precaution generates an obligation to continue.
Thomson, J. J. (1971). A Defense of Abortion. Philosophy & Public Affairs, 1(1), 47–66.
The scenario and what it adds
Thomson imagined a world where people-seeds drift through the air like pollen. If they land on your carpet and take root, they develop into people. This is how reproduction works in the scenario.
You want to open your windows for fresh air. You know the risk. You install fine-mesh screens. One seed gets through anyway, because no screen is perfect. It takes root in your carpet.
Are you now morally obligated to let it develop?
Thomson's point: you took precautions. You did not want this outcome. You were not reckless or indifferent. The seed is in your home because a reasonable precaution failed, not because you ignored the risk. She argued that in this case, the obligation to allow development is not obvious, and the seed's presence does not by itself generate an unlimited claim on your home and body.
This was Thomson's response to the most common objection to the violinist case: that voluntary action creates special obligations. The people-seeds scenario controls for that. You acted voluntarily, you took precautions, and the situation arose anyway. If obligation follows from voluntary action, it must be because the action was relevantly risky in a way that grounds the specific obligation, not merely because the action was voluntary.
The objection about the moral relationship
The most pointed response to the people-seeds analogy is that it mischaracterizes the relevant relationship.
A person-seed in your carpet stands in a different relationship to you than a developing fetus in a pregnancy. The biological and developmental relationship in pregnancy, whatever its ultimate moral weight, is not analogous to a seed that takes root in your living space. The use of property as a metaphor for bodily relations, critics argue, disguises morally relevant differences rather than illuminating them.
Thomson would say that the analogy doesn't need to be perfect to do its work. If the intuition that you're not obligated in the people-seeds case is strong, and if the scenario is structurally similar in the relevant respects to some cases of pregnancy, that intuition has evidential weight. Whether the relevant respects are actually similar is where the argument lives.
Discussion questions
- Does awareness of a risk change your moral obligations to deal with its consequences?
- Is the fact that the connection happened without your full consent enough to change what you owe the other person?
- Where do you draw the line between what you are obligated to do for another person with your body and what you are permitted to do?
Take it to the dinner table.
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