Ray is considered the "heart" of the Ghostbusters by the other members of the team. He is an expert on paranormal history and metallurgy. He is characterized by his almost childlike enthusiasm towards his work, and his forthright acceptance of paranormal activity.
Though he expresses skepticism toward Christianity, he is extremely knowledgeable about the Bible, even quoting a specific book and chapter--"I remember Revelation 7:12"-- about the end of the world (though the passage he quotes is actually Revelation 6:12).
He is known for his wordy and overly technical explanations of scientific and paranormal phenomena. Ray, along with Egon, is responsible for pioneering the Ghostbusters' theories and designing and building the equipment used for catching and containing ghosts.