Theory of Introjection

Theory of introjection was a fallacy advocated by R. Avenarius, the renown German empirio-criticism (Machism) supporter, which was used to slander the materialist theory of reflection. He argued that the materialist theory of reflection is to “introject” the outer world into human brain, he opposed that thoughts are the reflections of the material world and denied the materialist theory of reflection holding that a person’s correct thoughts include objective contents independent of the subject.

Avenarius claimed that materialism regards sensations and thoughts as reflections of the objective world in the human brain, which is intolerable “introjection”. He argued that sensations, thoughts and matters are inseparable, in principled coordination, and of substantiality, yet the materialist theory of reflection forcibly inputs sensations and thoughts into the inner world from the outer world, which is equivalent to turning external matters into perpectual ones and harming their substantiality. His thought was mere idealism.

The essence of Avenarius’ theory of introjection is to claim that thought is not a function of the brain and the brain is not the organ of thought, to denounce that thought is the reflection of the material world, to disagree that there are objective contents independent of the subject in a person’s correct thoughts, and thus to oppose the materialist theory of reflection. Avenarius’ theory of introjection is an attempt to overthrow the principle that consciousness is a reflection of the material world, so as to promote the “pure experience” without objective content and “pure thought” without mind proposed by empirio-criticism.

Lenin criticized Avenarius’ theory of introjection in his book Materialism and Empirio-Criticism, pointing out that “While distracting the attention of the reader by attacking idealism, Avenarius is in fact defending idealism, albeit in slightly different words”. He also added that “The doctrine of introjection is a muddle, it smuggles in idealistic rubbish and is contradictory to natural science, which inflexibly holds that thought is a function of the brain, that sensations, i.e., the images of the external world, exist within us, produced by the action of things on our sense-organs.”