Contents - Konrad Lorenz Institute

Of Brains and Minds
does not detract from the fact that all organisms,
whether they are simple reflex automata or active
and complex explorers, are above all concerned
with keeping track of their local spatio-temporal environment,
as part of their struggle for existence.
Since sensory information processing and the ability
to model reality (or certain parts of it) are essential
components in this process, our idea of problem
solving seems to correspond reasonably well to the
notion of intelligence.
However, the common use of the term ‘intelligence’
applies not only to processes involving complex
information processing (perception) but includes
operations of the ‘mind’ as well (see, e.g.,
DENNETT 1983; MACPHAIL 1985, 1993). It means that
if to a group of organisms no thoughts, intentions,
expectations and the like can reasonably be attributed,
they are considered to be creatures lacking in
intelligence. In order to avoid such subjective criteria,
intelligence in the present essay is defined as the
problem solving capacity of a species. It implies that
intelligence is not a quality restricted to the functional
domain of complex neural structures, but can
in principle be attributed to all organisms, from
amoeba to man.
Although each organism is equipped with an execution
potential which enables it to cope with a variety
of problems in a specified environment, there
are, of course, tremendous differences in the problem
solving capacity among living beings, and thus
in biological intelligence. Most of these differences
are connected with the functional characteristics of
the organism’s perceiving and executing apparatus.
A coelenterate, for instance, with its diffuse nerve fiber
network, has an action pattern which is of quite
a different order of magnitude as compared to the
rich behavioral repertoire of primates, with their
highly evolved central nervous system. Therefore, it
is only meaningful to compare the intellectual capacities
of species when they have certain basic features
in common.
The mammalian brain can be considered to be
such a structure, in that it is a multimodal integration
system composed of a highly efficient hybrid
device consisting of analogue neural units to process
information and a digital wiring system for information
transmission. In these highly organized
animals information from the external world passes
through three distinct stages or systems: a sensory
transducer system, a perceptual input system (or
systems) and finally a central cognitive system. During
this ‘journey’ the otherwise overwhelming
amount of sensory information is selected, analyzed,
integrated and stored in accord with the species’
attention and its needs and interests. It means
that the picture that an animal has of its external
world depends on (i) the quality of its sense organs,
(ii) its information processing capacity and (iii) its
informational and emotional states of mind. Consequently,
‘world pictures’ of animals must perforce
differ from each other, and can be looked upon as
highly individual representations of the external
world. Hence, it is appropriate to speak of speciesspecific
perceptual worlds (JERISON 1973, 1991) or
models of reality (WUKETITS 1986, 1990; RIEDL 1987;
PLOTKIN 1994).
Neural Worlds and Real Worlds
The idea of a species-specific model of reality corresponds,
to a certain extent, with KANT’s assumption
that the world as we know it is our interpretation of
the observable facts in the light of theories that we
ourselves invent (POPPER 1958; see also VOLLMER
1992). It means that models of reality, at least those
of higher vertebrates, are related to both the external
and the internal worlds and that it assumes the
existence of some knowledge in the form of dispositions
and expectations (POPPER 1972). The more
complete and reliable these knowledge-based specific
models are, the better the chance of survival. It
enables the animal to make better predictions, especially
predictions relating to features or situations
which do not occur in stereotyped patterns.
Though states of the brain represent states of the
external world we do not perceive reality precisely
as it is. The epistemological question now is how to
address the relationship between the neural world
and the real world. Perhaps representational models
in the brain are roughly like a map in the sense
that internal, abstract relationships map onto the
external relationships between various categories in
the world. According to this theory, put forward by
CHURCHLAND and CHURCHLAND (2002), brains develop
high-dimensional maps, the internal distance
relationships of which correspond to the similarity
relationships that constitute the categorial structure
of the world. The rough and low-dimensional
analogy is the road map of a city, in which the real
spatial relationships between roads are represented
in the relationships between road-lines on the paper
map. Just as road maps come in varying degrees
of reliablity and detail, so brain models of the external
world map the categorial and causal structure of
the world with varying degrees of reliablity and detail.
A frog’s brain maps less of the categorial struc-
Evolution and Cognition ❘ 179 ❘ 2003, Vol. 9, No. 2