Emily Bazelon talks with author Peter Singer about his updated and re-released book, Animal Liberation Now. The classic text has been an integral part of the animal rights movement since its publication in 1975. They discuss what we’ve learned about animals in the last several decades, including the intelligence of animals, why people should become vegan to help with climate change, and what we've learned about animals over the last four decades.

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Podcast production by Cheyna Roth.

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