Knowing precisely what drives necessity for the imaginary unit's presence in Quantum Theory resolves the question of quantum indeterminacy.

This chapter introduces ideas of logical independence.

Hans Reichenbach's 3-valued logic invokes the idea that quantum indeterminacy involves logical independence. Meaning and definition are given, and propositions used to represent experiments by Tomasz paterek et al: 'Logical Independence and Quantum Randomness' are cited as example. The role of logical independence in axioms systems is discussed. And ingression of logical independence through simultaneity or self-reference, also.