Stephen Hawking underwent a bronchotomy in 1985 due to complications such as muscle atrophy and pneumonia, breathing through a pipe inserted into his lungs, and then talking through a highperformance voice synthesizer attached to his wheelchair. Prior to that, he was able to speak vocally, and I found several videos of him speaking in the late 1970s. As an interest in how his interpreter was able to interpret his words, I made a video comparing the interpreted sentences with Hawking's words by adding subtitles.
ca. 1977, etc.