Peirce's "law of habit" extends the ordinary and scholarly concept of habit from human to nonhuman habits and to habits in the animate and the inanimate nature. It predicts that habits change by the habit of habit change and distinguished between habits, laws, rules, and norms. Human habits as habits of thought, action, and feeling and perception are phenomena of Firstness, Secondness, and Thirdness. With human habits, the habits of nature share the feature of plasticity. Peirce attributes the plasticity of habits also to the laws of cosmic and biological evolution and distinguishes laws as habits of nature from rigid laws that do not change. The paper also examines good habits in their contrast to bad ones and concludes with remarks on habit and habit change in semiosis.