Lhermitte's definition of illusions

   In 1951 the French psychiatrist Jean Lhermitte (1877-1959) defined "illusions as follows: "The illusion. This one is no longer a perception without material backup, without object, it is a deformed perception."

   References

   Lhermitte, J. (1951). Les hallucinations. Clinique et physiopathologie. Paris: G. Doin.