The package provides macros for typesetting natural deduction proofs in “Fitch” style, with subproofs indented and offset by scope lines.

The proofs from use of the package are in the format used in the textbook Language, Proof, and Logic by Dave Barker-Plummer, Jon Barwise, and John Etchemendy.

The author is Richard Zach. The package is Copyright © 2013 John Etchemendy, Dave Barker-Plummer, and Richard Zach.