What Problem Does It Solve?: It is hard to keep in mind all of the many different propositions that might bear on a complex factual dispute, much less to see the relationships between all competing propositions and the likely conclusions to be reached if one assumes certain facts to be true or false and certain propositions to be more or less reliable.

How Does It Do That?: By creating an explorable hierarchical structure that reflects all of the relationships between proposed facts and conclusions.

Why Is It Different? : Network diagrams use links between nodes. Argument arrows add the element of transitive links – connections that are applicable only across a number of different elements. Fish diagrams enforce a requirement that only one inference line can flow into a particular element. Argument arrows allow multiple incoming inference lines, including those that support or detract from the likely truth of the element in question. Argument arrows structures can be arbitrarily deep and can be explored upward or downward by clicking on elements of interest.

Who Will Use It? : Anyone seeking to record, see and understand the structure of a complex factual debate. For example, lawyers dealing with a complex set of disputed facts can use this kind of tool to keep track of all possible pieces of evidence and all the inferences that might be made from the evidence.

Other Potential Uses : Scholars engaged in debates about historical facts could use the tool to summarize the academic debate. And students could use the resulting structures to understand the debate and reach their own conclusions.

More Detailed Description : The Argument Arrows system is currently under development. The current system has been submitted to Marc Lauritsen for further analysis. Another version will be presented to John Clippinger for potential use in connection with complex policy/technical debates regarding open source authentication systems for the internet.

Lead Designer : David R. Johnson

Sponsors: New York Law School.

For More Information: email:;(202) 674-0187