Hawking, 71, told the British Broadcasting Corporation, "We don't let animals suffer, so why humans?" He stressed, though, that safeguards must be put in place.
"There must be safeguards that the person concerned genuinely wants to end their life and they are not being pressured into it or have it done without their knowledge or consent, as would have been done with me," he added.
Hawking, who has progressive motor neurone disease, was once put on a life support machine which his wife had the option of switching off, the BBC said.
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