This book is about "diamond", a logic of paradox. In diamond, a statement can be true yet false, an "imaginary" state, midway between being and non-being. Diamond's imaginary values solve many logical paradoxes unsolvable in two-valued Boolean logic. In this volume, paradoxes by Russell, Cantor, Berry and Zeno are all resolved. This book has three sections: Paradox Logic, which covers the classic paradoxes of mathematical logic, shows how they can be resolved in this new system, The Second Paradox, which relates diamond to Boolean logic and the Spencer-Brown "modulator" and Metamathematical Dilemma, which relates diamond to Gödelian metamathematics and dilemma games.