GOGAR (“the game of giving and asking for reasons”) is a simplified model of the discursive scorekeeping practice described in Robert Brandom’s book Making It Explicit (Cambridge: Harvard University Press, 1994). It is designed to help illustrate the way agents’ attributions of commitments and entitlements to each other is affected by the speech acts of making, disavowing, and challenging assertions.

GOGAR currently models only a part of the practice described in Chapter 3 of Making It Explicit, and it makes many simplifying assumptions. For example, it assumes that all the agents are in earshot of each other, so that testimonial inheritance of entitlements is universal.

The current version of GOGAR is a single Ruby script, gogar.rb. You can download the latest version here, or clone the git repository


After downloading and extracting gogar.rb, you can run it with the following command:

ruby gogar.rb

You may need to install Ruby first. There’s an installer for Windows here. Mac OSX comes with a version of ruby.

You can also run GOGAR as a web application, as follows:

ruby gogar.rb -w

By default, GOGAR will run on port 9094, so point your browser to http://localhost:9094/ and you should see it. An alternative port can be specified as follows:

ruby gogar.rb -w 7000

GOGAR carries no warranties of any kind.