Causal impotence objection

The causal impotence objection is among the most serious threats to ethical vegetarianism, action on climate change, and population mitigation. The argument begins with the premise that individuals, or relatively small collections thereof, have a negligible impact on the world; it is unlikely that their actions will make a substantive impact, or noticeably change some state of affairs. By the such individuals are not morally obligated to do anything about which they cannot control.

Examples

 * An individual riding a bike rather than a car makes no meaningful difference in overall carbon emissions. What difference they do make is generally so small as to be negligible and readily subsumed by the rest of society.


 * A lone individual abstaining from meat is unlikely to reduce any amount of animal suffering. The global market simply will not respond to one individual’s dietary choices, nor will most grocery stores, which are likely to purchase just as much meat as before.

Discussions
Philosopher rejects the “group principle” implicit in some arguments defending individual obligations based on collective impacts. Namely, by founding the individual obligation to do something on the collective impacts of a group, we merely beg the question of whether such an individual obligation exists.

Proposed resolutions
In regard to vegetarianism, and Peter Singer argue there must be some number of vegetarians at which some number of animals are spared a fate in factory farms. For example, 10,000 vegetarians might spare 200,000 chickens from factory farms per year (ignoring elasticities; note that the average American consumes roughly 27 chickens per year.) Assuming that the market responds to differences in demand of exactly 200,000 chickens, given the uncertainty about which decisions will actually lead to changes in supply, the expected number of chickens spared per whole chicken purchased would be 1. This is because, while each decision has a very low probability of leading to a shift in supply, when it does happen, the change is roughly 1 divided by that probability. So, the expected number of chickens spared per vegetarian per year would be 200,000 / 10,000 = 20.