Books that introduce one to the rigorous mathematical way of thinking. There are free and leisurely ones like Book of Proof by Richard Hammack. https://www.peo

Books that introduce one to the rigorous mathematical way of thinking. There are free and leisurely ones like Book of Proof by Richard Hammack. https://www.people.vcu.edu/~rhammack/BookOfProof/ https://www.people.vcu.edu/~rhammack/BookOfProof/