Tractatus Logico-Philosophicus · Chapter
5.143 explained
Wittgenstein distinguishes contradiction and tautology as extreme cases of propositions: contradiction is the external limit shared by no two propositions, while tautology is the substanceless center shared by all propositions.
What happens
Wittgenstein distinguishes contradiction and tautology as extreme cases of propositions: contradiction is the external limit shared by no two propositions, while tautology is the substanceless center shared by all propositions.
Themes in this chapter
Logic and Tautology
Tautology is described as the substanceless center shared by all propositions, highlighting its role in logical truth.
Nonsense and Meaning
Contradiction and tautology are shown as limiting cases that lack factual content, bordering on nonsense.
Characters to notice
- Mr. Wittgenstein
Author of the Tractatus; presents the logical distinction between contradiction and tautology.
Key passages
“Contradiction is something shared by propositions, which no proposition has in common with another.”
Contradiction is a property that belongs to propositions only when they are compared, but no single proposition contains it inherently.
Clarifies the relational nature of contradiction.
“Tautology is that which is shared by all propositions, which have nothing in common with one another.”
Tautology is the common logical form present in every proposition, even though propositions otherwise differ completely.
Emphasizes tautology as a universal logical feature.
“Contradiction vanishes so to speak outside, tautology inside all propositions.”
Contradiction is like an outer boundary that propositions cannot cross, while tautology is an empty core within each proposition.
Metaphor for the spatial limits of logical space.