Co- founder Russel Wallace and Charles Darwin agreed on many things about evolution however when it came to consciousness itself, Russel Wallace seen the mental as in a different realm of reality from biological processes.
Also Alfred Russel Wallace's views on natural selection differed from Charles Darwin's.
Charles Darwin emphasized competition between individuals of the same species to survive and reproduce, whereas Wallace emphasized environmental pressures on varieties and species forcing them to become adapted to their local environment.
Also Wallace had also envisioned natural selection as a kind of feedback mechanism keeping species and varieties adapted to their environment.
Alfred wrote a letter as well about spiritualism to his brother in- law in 1861, he wrote:
…I remain an utter disbeliever in almost all that you consider the most sacred truths. I will pass over as utterly contemptible the oft-repeated accusation that sceptics shut out evidence because they will not be governed by the morality of Christianity… I am thankful I can see much to admire in all religions. To the mass of mankind religion of some kind is a necessity. But whether there be a God and whatever be His nature; whether we have an immortal soul or not, or whatever may be our state after death, I can have no fear of having to suffer for the study of nature and the search for truth, or believe that those will be better off in a future state who have lived in the belief of doctrines inculcated from childhood, and which are to them rather a matter of blind faith than intelligent conviction.
In the summer of 1865, Alfred began investigating spiritualism, after reviewing the literature on the topic and attempting to test the phenomena he witnessed at séances, he came to accept that the belief was connected to a natural reality. For the rest of his life, he remained convinced that at least some séance phenomena were genuine, no matter how many accusations of fraud sceptics made or how much evidence of trickery was produced. Historians and biographers have disagreed about which factors most influenced his adoption of spiritualism.