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Post #2566011
2026-04-27 06:41 UTC
Proposition 98, p. 71: If πΆ follows π΄ and π΅ follows πΆ in the #TransitiveClosure of π
, then π΅ follows π΄ in the transitive closure of π
.
Hyp. β’ (π β π΄ β V)
Hyp. β’ (π β π΅ β V)
Hyp. β’ (π β πΆ β V)
Hyp. β’ (π β π΄(tcβπ
)πΆ)
Hyp. β’ (π β πΆ(tcβπ
)π΅)
Therefore β’ (π β π΄(tcβπ
)π΅)
βββ
Proposition 102, p. 72: If either π΄ and πΆ are the same or πΆ follows π΄ in the transitive closure of π
and π΅ is the successor to πΆ, then π΅ follows π΄ in the transitive closure of π
.
Hyp. β’ (π β π
β V)
Hyp. β’ (π β π΄ β V)
Hyp. β’ (π β π΅ β V)
Hyp. β’ (π β πΆ β V)
Hyp. β’ (π β (π΄(tcβπ
)πΆ β¨ π΄ = πΆ))
Hyp. β’ (π β πΆπ
π΅)
Therefore β’ (π β π΄(tcβπ
)π΅)
βββ
Proposition 106, p. 73: If π΅ follows π΄ in π
, then either π΄ and π΅ are the same or π΅ follows π΄ in π
.
Hyp. β’ (π β π΄π
π΅)
Therefore β’ (π β (π΄π
π΅ β¨ π΄ = π΅))
βββ
Proposition 108, p. 74: If either π΄ and πΆ are the same or πΆ follows π΄ in the transitive closure of π
and π΅ is the successor to πΆ, then either π΄ and π΅ are the same or π΅ follows π΄ in the transitive closure of π
.
Hyp. β’ (π β π
β V)
Hyp. β’ (π β π΄ β V)
Hyp. β’ (π β π΅ β V)
Hyp. β’ (π β πΆ β V)
Hyp. β’ (π β (π΄(tcβπ
)πΆ β¨ π΄ = πΆ))
Hyp. β’ (π β πΆπ
π΅)
Therefore β’ (π β (π΄(tcβπ
)π΅ β¨ π΄ = π΅))
βββ
Proposition 109, p. 74: If π΄ contains all elements of π and all elements after those in π in the transitive closure of π
, then the image under π
of π΄ is a subclass of π΄.
Hyp. β’ (π β π
β V)
Hyp. β’ (π β π΄ = (π βͺ ((tcβπ
) β π)))
Therefore β’ (π β (π
β π΄) β π΄)
βββ
Proposition 114, p. 76: If either π
relates π΄ and π΅ or π΄ and π΅ are the same, then either π΄ and π΅ are the same, π
relates π΄ and π΅, π
relates π΅ and π΄.
Hyp. β’ (π β (π΄π
π΅ β¨ π΄ = π΅))
Therefore β’ (π β (π΄π
π΅ β¨ π΄ = π΅ β¨ π΅π
π΄))
Replies (1)
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Proposition 111, p. 75: If either π΄ and πΆ are the same or πΆ follows π΄ in the transitive closure of π
and π΅ is the successor to πΆ, then either π΄ and π΅ are the same or π΄ follows π΅ or π΅ and π΄ in the #TransitiveClosure of π
.
Hyp. β’ (π β π
β V)
Hyp. β’ (π β π΄ β V)
Hyp. β’ (π β π΅ β V)
Hyp. β’ (π β πΆ β V)
Hyp. β’ (π β (π΄(tcβπ
)πΆ β¨ π΄ = πΆ))
Hyp. β’ (π β πΆπ
π΅)
Therefore β’ (π β (π΄(tcβπ
)π΅ β¨ π΄ = π΅ β¨ π΅(tcβπ
)π΄))
βββ
Proposition 122, p. 79: If πΉ is a function, π΄ is the successor of π, and π΅ is the successor of π, then π΄ and π΅ are the same (or π΅ follows π΄ in the transitive closure of πΉ).
Hyp. β’ (π β π΄ = (πΉβπ)) ; π΄ is the value of πΉ (implicitly assumed to be a function) at π such that π΄ is the unique value that π΄ immediately follows π, ππΉπ΄.
Hyp. β’ (π β π΅ = (πΉβπ))
Therefore β’ (π β (π΄(tcβπΉ)π΅ β¨ π΄ = π΅))
βββ
Proposition 124, p. 80: If πΉ is a function, π΄ is the successor of π, and π΅ follows π in the transitive closure of πΉ, then π΄ and π΅ are the same or π΅ follows π΄ in the transitive closure of πΉ.
Hyp. β’ (π β πΉ β V)
Hyp. β’ (π β π β dom πΉ) ; π is in the domain of relation πΉ
Hyp. β’ (π β π΄ = (πΉβπ))
Hyp. β’ (π β π(tcβπΉ)π΅)
Hyp. β’ (π β Fun πΉ) ; relation πΉ is a function
Therefore β’ (π β (π΄(tcβπΉ)π΅ β¨ π΄ = π΅))
βββ
Proposition 126, p. 81: If πΉ is a function, π΄ is the successor of π, and π΅ follows π in the transitive closure of πΉ, then (for distinct π΄ and π΅) either π΄ follows π΅ or π΅ follows π΄ in the transitive closure of πΉ.
Hyp. β’ (π β πΉ β V)
Hyp. β’ (π β π β dom πΉ)
Hyp. β’ (π β π΄ = (πΉβπ))
Hyp. β’ (π β π(tcβπΉ)π΅)
Hyp. β’ (π β Fun πΉ)
Therefore β’ (π β (π΄(tcβπΉ)π΅ β¨ π΄ = π΅ β¨ π΅(tcβπΉ)π΄))
Open ##2566012