The standard model of ethical theory may seem like merely a necessary consequence of applying to normative ethics the high standards of clarity and rigor prized by all of us who like to think of ourselves as philosophers in the analytic tradition. This way of doing ethics obviously parallels the way analytical philosophers treat many other subjects – by formulating generalizations about this or that and testing them against intuitive counterexamples. But I think the Sidgwickian method of intuitional ethics, or the Rawlsian method of reflective equilibrium, is not the only way to think clearly about ethical theory.

Kantian Ethics (2008) - Ch. 3. Ethical Theory