The maxim of refusing to assist others in pursuit of their projects passes the contradiction in conception test but fails the contradiction in the will test.
If your maxim fails the third step, you have a “perfect” duty admitting “of no exception in favor of inclination” to refrain from acting on that maxim (G 4:421). If your maxim fails the fourth step, you have an “imperfect” duty requiring you to pursue a policy that can admit of such exceptions. If your maxim passes all four steps, only then is acting on it morally permissible. Following Hill (1971), we can understand the difference in duties as formal: Perfect duties come in the form “One must n