The Replaceability Argument - Killing Happy Animals: Explorations in Utilitarian Ethics - page 50

is indeed relevant that the animal that one considers to kill would not
have existed if it were not for the purpose of ultimately being killed.
Pluhar and Sapontzis take the ceteris paribus clause to imply that the
killing causes no pain or fear for the animal nor any suffering for others,
such as mothers or mates. 3 Yet, if the killing would have such negative
consequences on welfare, this would not necessarily make the killing
and replacement impermissible. The negative welfare consequences for
the animal or its relatives that would be caused by the killing could be
outbalanced by the superior happiness of the animal that takes the place
of the previous one. Therefore, I will rather claim that the ceteris paribus
clause requires that the killing does not have any unbalanced negative
(side-) effects. Instead of taking this into a ceteris paribus clause, I will add
it as an extra condition.
These considerations lead me to the following definition of the
Replaceability Argument:
It is permissible to kill an animal, provided that the following condi-
tions are met:
(a) The future welfare of the animal would have been positive;
(b) The animal will be replaced, at or after death, by another animal,
whose lifetime welfare is at least as positive as the future welfare
of the killed animal would have been, and which would not
otherwise exist; and
(c) The killing does not have any unbalanced negative side effects
(such as fear or suffering for the animal or others).
This can be further specified according to any particular account of
welfare. For instance, on a hedonist account, one would say that
the future life of the animal should be pleasant overall. On a desire-
satisfaction account, one would say that the balance of the amount
of preference satisfaction minus the amount of preference frustration
should be positive.
Now that we are familiar with the conditions under which the
Replaceability Argument allows killing, it is interesting to find out
whether these conditions can be met in practice.
4 Can the conditions be met in practice?
At first glance, the Replaceability Argument clearly supports animal-
friendly animal husbandry. First of all, the animals in animal-friendly
animal husbandry are indeed assumed to have positive lifetime welfare .