V. I. Lenin

   
   
   Materialism and Empirio-Criticism (Moscow: Foreign Language Publishing
   House, no year given)
   
   
   
   "The fundamental premise of materialism is the recognition of the
   external world, of the existence of things outside and independent of
   our mind." (p. 78)
   
   
   
   "Did Nature Exist Prior to Man? We have already seen that this
   question is particularly repugnant to the philosophy of Mach and
   Avenarius. Natural science positively asserts that the earth once
   existed in such a state that no man or any other creature existed or
   could have existed on it. Organic matter is a later phenomenon, the
   fruit of a long evolution. It follows that there was no sentient
   matter, no 'complexes of sensations,' no self that was supposedly
   'indissolubly' connected with the environment in accordance with
   Avenarius' doctrine.. Matter is primary, and thought, consciousness,
   sensation are products of a very high development. Such is the
   materialist theory of knowledge, to which natural science
   instinctively subscribes." (p. 69)
   
   
   
   "We have seen that the starting point and the fundamental premise of
   the philosophy of empirio-criticism is subjective idealism. The world
   is our sensation--this is the fundamental premise. . . .The absurdity
   of this philosophy lies in the fact that it leads to solipsism, to the
   recognition of the existence of the philosophising individual only."
   (p. 89)
   
   
   
   "Yesterday we did not know that coal tar contained alizarin. Today we
   learned that it does. The question is, did coal tar contain alizarin
   yesterday?
   
   "Of course it did. To doubt it would be to make a mockery of modern
   science.
   
   "And if that is so, three important epistemological conclusions
   follow:
   
   "1)Things exist independently of our consciousness, independently of
   our perceptions, outside of us, for it is beyond doubt that alizarin
   existed in coal tar yesterday and it is equally beyond doubt that
   yesterday we knew nothing of the existence of this alizarin and
   received no sensations from it.
   
   "2) There is definitely no difference in principle between the
   phenomenon and the thing-in-itself, and there can be no such
   difference. The only difference is between what is known and what is
   not yet known. And philosophical inventions of specific boundaries
   between the one and the other, inventions to the effect that the
   thing-in-itself is "beyond" phenomena (Kant), or that we can or must
   fence ourselves off by some philosophical partition from the problem
   of a world which in one part or another is still unknown but which
   exists outside us (hume)--all this is the sheerest nonsense, Schrulle,
   crotchet, invention.
   
   "3)In the theory of knowledge, as in every other branch of science, we
   must think dialectically, that is, we must not regard our knowledge as
   ready-made and unalterable, but must determine how knowledge emerges
   from ignorance, how incomplete, inexact knowledge becomes more
   complete and more exact."
   
   (p. 98)