Let’s ask Robert Boyle, who in 1661 published The Sceptical Chymist, arguing that experiments disproved the idea that the universe was composed solely of Aristotle’s four elements. Boyle himself was an alchemist, in that he believed that one metal could be changed into another, but he was a staunch promoter of the scientific method and helped elevate chemistry to a science. So one could simply say that alchemy is a philosophy, while chemistry is a science.