The quality of being determined, definite, clear, and unwavering; the state of having firm boundaries or a fixed nature.
From determinate + -ness (noun suffix for states or qualities). Medieval philosophers used determinateness to describe things with clear, fixed natures versus things that could change.
Medieval scholars debated whether human souls had determinateness (fixed essence) or mutability (ability to change), using this very word—philosophy literally shaped the vocabulary of self-improvement.
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