Full Idea
Replacement of the categorical imperative by the natural imperative.
Gist of Idea
Replace the categorical imperative by the natural imperative
Source
Friedrich Nietzsche (Writings from Late Notebooks [1887], 09[27])
Book Reference
Nietzsche,Friedrich: 'Writings from the Late Notebooks', ed/tr. Bittner,Rüdiger [CUP 2003], p.146
A Reaction
This places Nietzsche rather firmly with evolutionary psychologists (who see morality in evolutionary terms), which he probably would not like. I just don't believe we are helpless victims of nature, and nor must we endorse what it asks of us.