Dr Goodall was asked to say his name, his date of birth and why he was at the clinic. He says he possibly will die by lethal injection, but that he would defer to doctors on the method.
Beethoven's 9th Symphony accompanied the former ecologist as he drifted into sleep.
The ecologist, who was born in England and moved to Australia, also had a final meal of fish and chips with cheesecake for dessert. They were taken from the "Ode to Joy", a poem written by Friedrich Schiller in 1785 and revised in 1803, with additions made by the composer.
He died at the moment the song concluded, said Exit International - a campaign group that helped Dr Goodall travel to the clinic.
"I have serious concerns about a community where we make arbitrary decisions about whose life is valuable enough to continue and whose should be ended under the law", he added.
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Four family members and a close friend had travelled to be at his side when he ended his life.
"At my age, and even at rather less than my age, one wants to be free to choose the death and when the death is the appropriate time".
Earlier this year, however, Goodall fell while home alone in his one-bedroom apartment and remained on the floor for two days until he was found by his cleaner, The New Daily reported.
While not terminally ill, Goodall told reporters from across the globe that he had simply stopped enjoying life at his advanced age.
The 104-year-old scientist was administered the drug Nembutal.
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His last words before losing consciousness were: 'This is taking an awfully long time.' He died at 12.30pm in Liestal where he took advantage of Swiss assisted-suicide laws.
Modern medical practice is very focussed on curing people but struggles to confront the suffering where death is inevitable and unavoidable. The singular Australian state to allow euthanasia is Victoria, but the option is legally available there only to terminally ill individuals.
He wrote dozens of scientific works and until recently was still working as a columnist and editor for several environmental journals.
Once named Australia's oldest working scientist, Goodall wished for his body to be donated to medicine or, alternatively, that his ashes be sprinkled locally. He did not believe in an afterlife, the organization said.
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