The Microsoft co-founder, who co-chairs the Gates Foundation, often writes about what he’s reading on his blog Gates Notes. On Monday, he continued his annual tradition of sharing a summer reading list by posting five book recommendations. “I realized that several of my choices wrestle with big questions,” he said of the list, which includes a biography, memoir, and Man Booker Prize-winning novel. “Despite the heavy subject matter, all these books were fun to read, and most of them are pretty short.”

Take a look at Gates’ recommendations—and the video he posted about them—below:

Leonardo da Vinci by Walter Isaacson

Biographer Walter Isaacson, who also wrote 2011’s Steve Jobs, along with biographies of Albert Einstein and Benjamin Franklin, tackles the Renaissance man’s story by connecting da Vinci’s art and science. “Isaacson does the best job I’ve seen of pulling together the different strands of Leonardo’s life and explaining what made him so exceptional,” Gates noted in his blog. Readers may not consider this 600-page book particularly short.

Everything Happens for a Reason and Other Lies I’ve Loved by Kate Bowler

Written by a historian at the Duke Divinity School, this memoir addresses the author’s diagnosis of stage IV colon cancer and her attempts to understand why it happened to her—and whether it was some kind of test. Gates, who said Bowler’s work belongs on bookshelves along with similar books such as Atul Gawande’s Being Mortal and Paul Kalanithi’s When Breath Becomes Air, said the memoir manages to be both heartbreaking and funny.

Lincoln in the Bardo by George Saunders

The novel, which won the Man Booker Prize in 2017, is a work of historical fiction that tackles Abraham Lincoln’s grief over losing his son. “I thought I knew everything I needed to know about Abraham Lincoln, but this novel made me rethink parts of his life,” said Gates, adding that it’s the type of book that will make readers want to discuss it even further with a friend.

Origin Story: A Big History of Everything by David Christian

Origin Story, written by the creator of the Big History Project, a free online course that “spans 13.8 billion years,” addresses everything from the start of the universe to modern-day society, as well as what the future may hold. “If you haven’t taken Big History yet, Origin Story is a great introduction. If you have, it’s a great refresher,” Gates wrote.

Factfulness by Hans Rosling, with Ola Rosling and Anna Rossling Ronnlund

Hans Rosling, a Swedish physician and statistician, died last year, but he collaborated with his son and daughter-in-law on this book, which delves into—as Gates puts it, “understanding basic truths about the world—how life is getting better, and where the world still needs to improve.” Gates called the book one of the best he’s read, calling it a “fitting final word from a brilliant man.”