At a conceptual level, the difference is clear. Criticism marshals evidence and arguments in a rational effort to persuade. Canceling, by contrast, seeks to organize and manipulate the social or media environment in order to isolate, deplatform or intimidate ideological opponents. It is about shaping the information battlefield, not seeking truth; and its intent—or at least its predictable outcome—is to coerce conformity and reduce the scope for forms of criticism that are not sanctioned by the prevailing consensus of some local majority.
In practice, however, telling canceling apart from criticism can be difficult because both take the form of criticizing others. That is why it is probably impossible to devise a simple bright-line test of what should count as a harmful instance of cancelation.
A better approach might therefore be diagnostic. Like the symptoms of cancer, the hallmarks of a cancellation are many. Though not all instances involve every single characteristic, they all involve some of its key attributes. Rather than issuing a single litmus test, the diagnostic approach allows us to draw up a checklist of warning signs. The more signs you see, the more certain you can be that you are looking at a cancel campaign.
Six warning signs make up my personal checklist for cancel culture.