Ch. 4— Ethical Considerations • 77 
accordingly, recanted his earlier references to the 
language of rights (46): 
I could easily have dispensed with it altogether. 
I think that the only right I ever attribute to ani- 
mals is the "right” to equal consideration of inter- 
ests, and anything that is expressed by talking of 
such a right could equally be expressed by the 
assertion that animals’ interests ought to be given 
equal consideration with the interests of humans. 
Singer effectively acknowledges Hart's charge that 
the notion of a right has lost its distinctive func- 
tion in this context because it no longer refers to 
the discretionary control that one individual has 
over the conduct of another. 
There is one very general consideration that ap- 
pears to weigh against the will theory, if not en- 
tirely in favor of the interest theory. It underlies 
a form of argument so ubiquitous in the animal - 
rights literature that it deserves a name. The con- 
sistency argument is exemplified in the following 
passage from an essay on vegetarianism by Tom 
Regan. Rejecting rationality, freedom of choice, 
and self-consciousness as conditions for having a 
right to life, Regan adds (41): 
It is reasonably clear that not all human beings 
satisfy them. The severely mentally feeble, for 
example, fail to satisfy them. Accordingly, if we 
want to insist that they have a right to life, then 
we cannot also maintain that they have it because 
they satisfy one or another of these conditions. 
Thus, if we want to insist that they have an equal 
right to life, despite their failure to satisfy these 
conditions, we cannot consistently maintain that 
animals, because they fail to satisfy these condi- 
tions, therefore lack this right. 
Another possible ground is that of sentience, 
by which I understand the capacity to experience 
pleasure and pain. But this view, too, must en- 
counter a familiar difficulty— namely, that it could 
not justify restricting the right only to human 
beings. 
In short, given that some human beings (infants, 
mental defectives, and senile adults) lack such ca- 
pacity as well, Regan points to the inconsistency 
of holding both that this capacity is a condition 
of having a right and that all humans and only hu- 
mans have moral rights. Any less burdensome test, 
however, will presumably admit animals as possi- 
ble right-holders (33,45). (For an opposing perspec- 
tive, see refs. 22 and 24.) 
This reasoning appears to overlook a significant 
difference between an incompetent human being 
and an animal. In most cases, human beings have 
the capacity for rationality, freedom of choice, and 
self-consciousness, whereas in all cases animals 
do not. If most humans have these characteristics, 
it might be appropriate (or at least convenient) to 
treat humans as a homogenous group, even though 
some members lack these characteristics. If all 
animals lack certain characteristics, it may be sim- 
ilarly appropriate to treat them as a group, re- 
gardless of whether some humans also lack these 
characteristics. 
Furthermore, if rights do not imply present pos- 
session of the qualifying condition (as suggested 
by the way that people treat those who are men- 
tally incapacitated only for a time), then babies who 
have yet to mature and people who have become 
incapacitated after a period of competence will 
still have rights. The animal, as far as can be ascer- 
tained, has never met and will never meet this qual- 
ification. The rare human being whose deficiency 
is complete over a lifespan is nevertheless differ- 
ently situated from the animal. The condition is 
a disability— the loss of some skill the person would 
normally be expected to have. The animal’s con- 
dition is not disabling, even though it lacks the same 
skill. The very fact that the human has been de- 
prived of an ability implies that the person has been 
harmed; a human’s failure to acquire an ability 
means that person is in need of help. The condi- 
tion of the animal does not call for either infer- 
ence. This difference, to be sure, makes no men- 
tion of rights. Yet it creates a special duty to meet 
the human need that would not extend to animals . 
Because the animal without a will has not lost what 
it was biologically programmed to possess, it "needs” 
a will only as a human might "need” to fly. In nei- 
ther case does the condition give rise to a moral 
demand for assistance. 
Ironically, the consistency argument contains 
a basic inconsistency. On the one hand, the argu- 
ment asserts that humans are not superior to ani- 
mals; animals should therefore be treated like hu- 
mans. On the other hand, the very nature of the 
moral argument is promotion of morally superior 
behavior: Humans should refuse to exploit other 
species, even though the other species exploit each 
other. 
