e34.
Keller, introduction to part 2 of Keller, ed. (2010), p 59. Immanuel Kant, “Duties Towards Animals and Spirits”, c.1784, reprinted in Keller, ed. (2010), as reading 7. Probable date based on Georg Ludwig Collins’ notes on the lectures which he attended at the University of Königsberg in that year (in Immanuel Kant, Lectures on Ethics, Peter Lauchlan Heath and Jerome B. Schneewind, eds. (2001), Cambridge University Press).