Alfred Russel Wallace was born in the Welsh village of Llanbadoc in 1823, and became a naturalist, geographer, anthropologist, and biologist. He is best known for independently conceiving the theory evolution and co-publishing with Charles Darwin in 1858. Wallace was also a social activist who was critical of the unjust social and economic system in Britain. He was one of the first prominent scientists to raise concerns over the human impact on the environment. He wrote on both scientific and social issues, and documented his travels to Singapore, Indonesia, Malaysia and the Malay Archipelago.

Wallace was introduced to occult phenomena when he attended a demonstration on mesmerism (hypnosis) given by a Mr. Spencer Hall in 1844. Although a nonbeliever at the start, he found himself able to induce the same effects with his own subjects and eventually became a skilled hypnotist.

Wallace began investigating spiritualism in 1865. After reviewing the literature and attempting to test what he witnessed at seances, he concluded that the practice illustrated a natural phenomenon. For the rest of his life, he remained convinced that at least some séances were genuine, no matter how many accusations of fraud skeptics made or how much evidence of trickery was produced.

For Wallace, spiritualism was a matter of science and philosophy rather than religious belief. In 1893, he wrote: “I thus learnt my first great lesson in the inquiry into these obscure fields of knowledge, never to accept the disbelief of great men or their accusations of imposture or of imbecility, as of any weight when opposed to the repeated observation of facts by other men, admittedly sane and honest. The whole history of science shows us that whenever the educated and scientific men of any age have denied the facts of other investigators on a priori grounds of absurdity or impossibility, the deniers have always been wrong.”

In 1874, Wallace visited the spirit photographer, Frederick Hudson, who had been called fraud two years before. After Wallace saw the photo of himself and his deceased mother, he declared it genuine.  He said, “even if he had by some means obtained possession of all the photographs ever taken of my mother, they would not have been of the slightest use to him in the manufacture of these pictures.

Wallace’s views on spiritualism occur in many his writings. He reached four conclusions. First, a human being’s individual existence extends beyond biological death. Second, conscious existence during this period is determined by the level of intellectual and moral development attained during one’s life. Third, intellectual and moral development is a function of free-will. Fourth, there is a continuity of cause and effect in nature which cannot be avoided.

Wallace’s advocacy of Spiritualism damaged his scientific reputation and affected the public perception of his work.He was never able to secure a permanent position, like museum curator. He graded government examinations, wrote papers for small sums, and help Darwin edit his work for a fee. He died in 1913 at the age of 90 in his country house.