Evolutionary biologist and atheist author Richard Dawkins has argued that simply refusing to have sex is comparable to aborting an unborn baby.
"How dare you refuse to have sex? Don't you realise you might be depriving a baby of life? Murderer!" Dawkins wrote in a Twitter message, as part of an ongoing debate over the morality of abortion and when human life begins.
When asked by Twitter users to explain when he believes life actually begins, Dawkins replied, "It doesn't begin. That's the whole point," and directed people to read his 2011 article for New Statesman titled, "The Tyranny of the Discontinuous Mind."
In the article, Dawkins argues against the idea that life begins at conception, and says that reality is not black or white, where an embryo is either human or it isn't.
"For purposes of legal clarity, just as the eighteenth birthday is defined as the moment of getting the vote, it may be necessary to draw a line at some arbitrary moment in embryonic development after which abortion is prohibited. But personhood doesn't spring into existence at any one moment: it matures gradually, and it goes on maturing through childhood and beyond," The God Delusion author wrote at the time.
He said that there are a number of examples across many areas of life that also don't have either-or answers, such as trying to determine a person's race if he or she has both black and white ancestors.
Throughout the years Dawkins has been challenged on a number of his views on abortion, and has at times apologized for controversial remarks he has made on the topic.
Back in August 2014, Dawkins suggested that parents who are pregnant with a Down syndrome baby need to abort the fetus.
"Abort it and try again. It would be immoral to bring it into the world if you have the choice," the evolutionary biologist Tweeted back then.
His remarks prompted wide-spread backlash, with several people posting photos of loved ones with Down syndrome.
Pro-Life activist Lisa Rose said that "it's sick and twisted for anyone to advocate for the killing of children with disabilities."
"Dawkins' ignorant comments serve only to further stigmatize people with Down syndrome," she added.
Dawkins said that he apologize for the controversy, and tried to clarify his views:
"Of course, I regret using abbreviated phraseology which caused so much upset. I never wanted to 'cry havoc,'" he said, but added that once "Down syndrome is detected, most couples opt for abortion and most doctors recommend it."