The Concise Oxford Dictionary of World Religions (1628 page)

g
rjuna argued that these too are empty of self (
dharmanair
tmya
), and are not independent constituents of appearance: they depend on each other and have no more reality than their interdependence. All dharmas are
m
y
(dreamlike appearance).
However, appearances have at least that much existence—they appear to be. Thus N
g
rjuna charts the Middle Way between substance and solipsism. The ‘thusness’ (
tathat
) of what is cannot be described but only realized, as undifferentiated in nature. Therefore even
nirv
na
and
sa
s
ra
have the same nature (‘there is not the slightest difference between the two’)—they are not other than each other, since all is empty of self. In that sense, all oppositions between nirv
na and sa
s
ra, heaven and earth, icon and index, disappear.
The purpose of a wise life, therefore, is not to strive to attain some goal or target (heaven, enlightenment), but to uncover and discover what one already is, and has been all the time: the buddha-nature which is the same nature of oneself and all appearance (see
BUDDHAT