Richard is an ethologist, evolutionary biologist, and author. He is a vocal atheist and naturalist. He grants moral consideration to sentient non-humans in principle and hopes for a vegan world, as you can hear in these discussions (with Sentientist Peter Singer and in this talk). In practice he continues to buy and consume sentient animal products and his compassion for human sentient beings has been criticised as conditional. The Center for Inquiry, where Richard is a founding board member, published this article about Sentientism in their Free Inquiry magazine.
Richard on Wikipedia
@RichardDawkins

Sam is an author, neuroscientist, and podcast host. Sam’s book, The Moral Landscape, sets out a naturalistic ethics that is largely consistent with Sentientism, in that it grants moral consideration to conscious non-human as well as human beings. However, despite experimenting with vegetarianism and veganism, Sam continues to buy and consume products made from sentient beings, implying he doesn’t personally grant them meaningful moral consideration. He is a vocal atheist and naturalist.
Sam on Wikipedia
@SamHarrisOrg

Carl was an astronomer, planetary scientist, cosmologist, astrophysicist, astrobiologist, author and science communicator. He had a robustly naturalistic worldview. He said: “I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But as much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife I know of nothing to suggest that it is more than wishful thinking.”
He counselled against anthropocentrism (centring too strongly on the human species). He called on humans “to extend our ethical perspectives downward through the taxa on Earth and upwards to extraterrestrial organisms, if they exist.”However, he was not vegan or even vegetarian, implying that, in practical terms, he didn’t extend meaningful moral consideration to sentient farmed animals.
Article: “Sciences vast cosmic perspective eludes religion”
Carl on Wikipedia

Jeremy is a politician who served as Leader of the Labour Party and Leader of the Opposition from 2015 to 2020. He has been the Member of Parliament (MP) for Islington North since 1983. Jeremy says he is sceptical about having God in his life. He is vegetarian. However, he has denied being an atheist and has compared his environmental concerns to a sort of “spiritualism”. This implies he does not have a naturalistic worldview.
Jeremy on Wikipedia
@jeremycorbyn

Michael is an American science writer, historian of science, founder of The Skeptics Society, and editor-in-chief of its magazine “Skeptic”. Michael is an advocate for naturalism and skepticism. While he has acknowledged that animal farming may come to be looked on by future generations as a moral abomination or holocaust, he continues to purchase and consume animal products.
From this 2016 Salon article: “Michael Shermer, author of ‘The Moral Arc,’ tweeted, ‘Ugh. Watched The Earthlings last night researching moral progress. Feels like moral regress when it comes to animals,’ as well as writing an article titled ‘“Confessions of a Speciesist.’ However promising these signs were, sadly he has also admitted, ‘No I’m not a vegetarian but think we should expand the moral sphere to include marine mammals and all primates as a good start.’”
Michael on Wikipedia
@michaelshermer
michaelshermer.com

“The reasons we articulate today for animals to have rights, we will need in the future, to convince superintelligent AIs to allow us to keep our rights.”
Roman’s Sentientist Conversation with Jamie on YouTube and on the Sentientism Podcast
Roman on Wikipedia
Roman on GoogleScholar
@romanyam