In most general terms,

ries deployed by the thick interpretation. In most general terms, what
happens at 9 months is a fundamental change in the nature of the infant’s
interactions with people and objects. I have noted that in the first 9
months of life infants engage in surprisingly complicated social interactions
with their caregivers. The same period is also one of keen exploration
and manipulation of physical objects. The consensus of opinion
among workers in the area is that what is distinctive of infant behavior
and cognition in the first 9 months of life is an inability to integrate these
two different types of interaction. These young infants can interact with
other people in the protoconversational manner described, and they can
explore and manipulate objects, but they can only do one task at a time.
What happens at 9 months is that infants suddenly become capable, not
just of undertaking both types of interaction at the same time, but also
of coordinating them in a way that creates a fundamentally new type of
interaction. This new type of interaction is triadic rather than dyadic.
Infants become capable of employing their interactions with people in
their interactions with objects, and vice versa. Figure 9.1, drawn from
Tomasello 1993, illustrates the general structure of the transition. In the
remainder of this chapter I will examine three of the new social interactions
made possible by this transition from dyadic to triadic interactions.
What I will argue to be the best explanation of these interactions involves
ascribing to the infants involved the distinguishing psychological selfawareness
discussed above. To each of the three types of interaction there
corresponds one strand of the core notion of a psychological subject identified
in the previous section.
The first type of social interaction has been well studied by developmental
psychologists as the phenomenon of joint selective visual attention.
Joint visual attention is the simplest form of triadic interaction, and
the basis of the other two that I shall consider. Joint visual attention occurs
when infants attend to objects as a function of where they perceive
another individual’s gaze to be directed and, conversely, when infants direct
another individual’s gaze to an object in which they are interested.
Let me briefly review the respective evidence for these two aspects of joint
visual attention.
I begin with the evidence for the infant’s ability to look to where they
perceive another individual’s gaze to be directed. Scaife and Bruner (1975)
ith an experimenter (not a caregiver) who established eye contact with
them and then looked away. The aim was to find the age at which infants
followed the movement of the experimenter’s gaze at a level above chance.
The group of infants aged 8 months and over performed considerably
better than chance—a particularly significant result in view of the infant’s
lack of familiarity with the experimenter and the artificiality of the paradigm.
Murphy and Messner (1977) showed that 9-month-old infants are
capable of recognizing maternal pointing as a cue for directing their attention.
Although their ability at that age to follow the invisible line from
the pointing hand to the target object is subject to certain limitations (particularly
when there is a large angle of separation between the pointing
limb and the target object and when there are distracting features), the
infants were clearly able to register that their attention is being directed
Infant Adult
Object
(or anywhere else)
Infant Adult
Object
Infant Adult
Object
Infant Adult
Object
Before 9 months of age
After 9 months of age
(a) Infant engagement with object prior
to 9 months (adult passive onlooking)
(b) Infant engagement with person prior to
9 months (object not part of interaction)
(c) Joint attention after 9 months (d) Self-perception after 9 months
256 Chapter 9
Infants’ engagements with objects and persons before and after 9 months of age.
Solid arrows indicate perception and dashed arrows a comprehension of another’s
perspective. (From Tomasello 1993, 177.)
toward the target object. There is evidence also that infants, after following
the direction of the point, look back at the person pointing for feedback
as to whether they have indeed targeted the right object. The
implications of these and other findings (Bruner 1975) are summed up by
Jerome Bruner in these terms:
What has been mastered at this first stage is a procedure for homing in on the
attentional locus of another. It is a disclosure and discovery routine and not a
naming procedure. It is highly generative within the limited world inhabited by
the infant in the sense that it is not limited to specific kinds of objects. It has,
moreover, equipped the child with a technique for transcending egocentrism, for
insofar as he can appreciate another’s line of regard and decipher their marking
intentions, he has plainly achieved a basis for what Piaget has called decentration,
using a coordinate system for the world other than the one of which he is the
centre. (Bruner 1977, 276)
The converse aspect of joint visual attention, the crucial embedding of
object-focused attention in social contexts, begins at about the age of 6
months when infants begin to switch their gaze back and forth between
object and caregiver (Newson and Newson 1975). These gestures develop
during the last third of the first year into attempts on the part of the infant
to establish an object as the focus of joint attention (Leung and Rheinhold
1981). Daniel Stern provides an eloquent summary of how infants can
take the initiative in generating states of joint visual attention:
Infants begin to point at about nine months of age, though they do so less frequently
than mothers do. When they do, their gaze alternates between the target
and the mother’s face, as when she is pointing to see if she has joined in to share
the attentional focus. It seems reasonable to assume that, even prior to pointing,
the infant’s beginning capacity to move about, to crawl or cruise, is crucial in
discovering alternative perspectives as is necessary for joint attention. In moving
about, the infant continually alters the perspective held on some unknown stationary
sight. Perhaps this initial acceptance of serially different perspectives is a
necessary precursor to the more generic “realization” that others can be using a
different coordinate system from the infant’s own. (Stern 1985, 129–130)
It is interesting to consider the conclusions that Stern draws from the
development of these two aspects of joint visual attention:
These observations lead one to infer that by nine months infants have some sense
that they can have a particular attentional focus, that their mother can also have
a particular attentional focus, that these two mental states can be similar or not,
and that if they are not they can be brought into alignment and shared. Interattentionality
becomes a reality. (Stern 1985, 130)