A consciousness without an object is no consciousness.
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

add
Author Arthur Schopenhauer
Source The World as Will and Representation
Topic consciousness
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/40097/40097-h/40097-h.html

Context

““the subject would still remain a knowing being if it had no object, i.e., if it had absolutely no idea,” is just as false as the assertion of the crude understanding, “the world, the object, would still exist, even if there were no subject.” A consciousness without an object is no consciousness. A thinking subject has conceptions for its object; a subject of sense perception has objects with the qualities corresponding [pg 179] to its organisation. If we rob the subject of all special characteristics and forms of its knowledge, all the properties of the object vanish also, and nothing remains but matter without form and quality, which can just as little occur in experience as a subject without the forms of its knowledge, but which remains opposed to the naked subject as such, as its reflex, which can only disappear along with it.” source