BODY AND PRACTICE IN KANT

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CAUSALITY AND COMMON SENSE PHYSICS
now use Piaget as a guide. More specifically, when we find a practice
claimed by Piaget to have the same cognitive function as the relational
categories have according to Kant, then we may argue that this practice
is what we are looking for, i.e. it is where the category is present qua
practice. In what follows, I shall do that.
11.3 Sensorimotor practices and the relational categories
In the first analogy Kant explains the fact that we think of the objects of
our experience as permanent by referring to the category of substance.
Thus the category of substance accounts for the fact that we ascribe to
objects existence also in the periods when they are not immediately
perceived. According to Piaget, the child shows it has a sensorimotor
understanding of object-permanence when, for instance, it is found
searching for an object, including when this object is not immediately
perceived. Actually, according to Piaget, to entertain this and similar
practices is what it means at this level to know that objects have a
permanent existence. There is no knowledge of object-permanence
independent of and external to these practices. This means that if we
accept that there is a sense in which the child at this level experiences
itself to be living in a world of permanent objects, this experience is made
possible by the above suggested practices. The practices are a priori
conditions for possible experience in this specific sense. Let us assume
that all these practices are versions of one general practice, and let us call
this ‘the practice of object-permanence’.
The reason why I suggest that this general practice may be present in
more than one version is that I do not want to confine attention only to
those specified above, i.e. the practice of searching for an object,
including when this object is not immediately perceived. Actually, I think
that any act in which we adjust our behavior to the world of objects so
that certain desired ends are produced and others are avoided may be
seen as an example of the same general practice. An instance of this may
be when the child grasps and explores an object. Thus, I think that an
original, primitive sensorimotor knowledge of object-permanence is
found when the child first learns to grasp a ball or another object placed
before it.
In an earlier chapter I used the example of a person exploring a ball
to illuminate the idea that space is transcendentally ideal. Let us return to
this example, however, and now imagine that the person in question is a
child in the sensorimotor period. Let us also try to describe the event in
Kantian terminology. Transcendentally considered, what we call the
spatial shape of the ball is the awareness the child has of the movements