It is not that the two views explicitly give conflicting answers to any of the three questions in section 1: while the psychological-continuity view is an answer to question a, the ques-
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to abandon it altogether During the past two decades, however, many so-called
“animalists” have claimed to offer just such a reason
According to animalism, human persons are human animals, members of the
species Homo sapiens (Ayers 1991; Carter 1988; Mackie 1999a; Olson 1997;
2003; Snowdon 1990; 2014; van Inwagen 1990) This view may seem too obvi-ous to be worth stating: who believes that we are plants or dogs or robots? But animalism is not trivial, for it is incompatible with the psychological-continuity view (as well as with various other popular theories) It is not that the two views explicitly give conflicting answers to any of the three questions in section 1: while the psychological-continuity view is an answer to question (a), the ques-tion about our persistence condiques-tions, animalism is an answer to quesques-tion (c), the question of what kind of thing we are However, psychological continuity – with
or without the “non-branching” qualification – is not necessary and sufficient for a
human animal’s identity over time, and so if we are human animals, as animalism says, it is not necessary and sufficient for our identity over time, contrary to the
psychological-continuity view (Olson 1994; 1997; 2003)
To see that psychological continuity is not necessary for the identity over time
of a human animal, note that every human animal was once an embryo, which did not have any psychological features whatsoever, and hence was not psychologi-cally continuous with anything at all Moreover, if the animal is unlucky, it might enter a permanent vegetative state, in which it is still alive but has no psychological features.14 To see that psychological continuity is not sufficient for the identity over time of a human animal, return once again to the Brownson case After the transfer, the “recipient” animal (the one with what was Brown’s brain before the transfer) is psychologically continuous with the “donor” animal (the one that started out with Brown’s brain) as it was before the transfer But surely these are two different ani-mals; the surgeons have moved an organ, not an entire human organism.15
So if the psychological-continuity view is true, then we are not human ani-mals This is troublesome for the psychological-continuity view, for there is an influential argument in favor or animalism: the “thinking animal problem,” most forcefully put forward by Eric Olson (1997, 80–91, 97–109; 2003; 2007, 29–39)
It begins with the simple observation that, whether or not I am a human animal,
there is a human animal where I am It is the organism that I see when I look in
the mirror, and is currently sitting comfortably in my chair This animal is suspi-ciously like me: if it is not me, then it is hiding it very well This comes out most clearly when we consider the animal’s mental properties Because the animal and
I have the same brain (or at least exactly similar brains, located in the same place and composed of the same particles), and the same surroundings, it seems that it must be psychologically indiscernible from me Olson argues that if I am
nonethe-less not it, then three problems arise First, there is a problem of too many
think-ers If I am not the animal, then
[t]here are two thinking beings beings wherever we thought there was just one There are two philosophers, you and an animal, sitting there