KNOWLEDGE
EVOLUTION
Figure 1
1. The Cartesian Perspective
Cartesian definition of ‘idea’ rests on the notion of ‘simple nature’ (natura simplicissima;
res simplex). Since the absolute form of reality is a myth, what we understand as ‘real’ is
not at all the invariant core of the existence rather it is the ‘essence’ (ousia) of it. We will
label it as ‘umbra’ that metaphorically means the shadow of the invariant existential core.
Umbra is the object of our knowledge. It is not something which is prior and absolute to
start with rather it is the end - a projection of the underlying ‘reality’ of the nature-
absolute. The mental image, again metaphorically, can now be viewed as the ‘penumbra’,
because of being a projection of umbra. ‘Simple nature’ is all about the penumbra. In the
post Cartesian epistemological revolution, ‘idea’ is defined as an object that is primary in
respect to our knowledge and neither in respect to its ‘essence’ (= umbra), nor in respect
to the nature-absolute.
‘Idea’, as a ‘simple nature’, can be classified into three broad categories, namely
‘purely intellectual’, ‘purely material’ and ‘common notions’ (notiones communes) or
‘principles of logic’. Common notions are of two types. The first one designates an
‘idea’, which, irrespective of being a member either to intellectual or to material simple
nature, stands by itself, such as existence, unity etc. (Marion 1992). Thus, known as
‘real’. This ‘real-common-simple nature’ is analogous with the ‘axiom’. On the other
hand, the second one defines an ‘idea’ which stands only in relation to the other and
hence ‘logical’. ‘Logical-common-simple nature’ in later period of development turns up
as ‘theorem’. We have some vague idea that some of these theorems are basic than the
others, and hence considered as axioms. None of us, however, can claim what theorems
are truly fundamental (Wilson 2003).
1.1. res extensa vs. res cogitans
The main Cartesian concern was all about ‘material-simple nature’. This concern
ultimately leads towards the whole gamut of scientific enterprise. As a result,
‘intellectual-simple nature’ remains untouched, since it has been believed that intellectual
simple nature requires reasoning of a purely intellectual kind, conducted in abstraction