Contrastivism

Contrastivism is an epistemological theory proposed by Jonathan Schaffer that suggests that knowledge attributions have a ternary structure of the form 'S knows that p rather than q'. This is in contrast to the traditional view whereby knowledge attributions have a binary structure of the form 'S knows that p'. Contrastivism was suggested as an alternative to contextualism. Both are semantic theories that try to explain skepticism using semantic methods.

Read more about Contrastivism:  The Contrast Clause, References and Further Reading