Sequiturs is a web app for developing rigorous, digestible arguments on any topic.

An argument is a series of premises and conclusions. Arguments can build on each other, by using the conclusion of one argument as a premise in another argument. Arguments can challenge each other, by marking the conclusion of one argument as contradicting a premise or conclusion in another argument.

UPDATE: Sequiturs has been discontinued and is no longer active at https://sequiturs.ai.