Theorem List for Intuitionistic Logic Explorer - 16801-16807 *Has distinct variable
group(s)
| Type | Label | Description |
| Statement |
| |
| Definition | df-alsi 16801 |
Define "all some" applied to a top-level implication, which means
𝜓
is true whenever 𝜑 is true and there is at least one
𝑥
where
𝜑 is true. (Contributed by David A.
Wheeler, 20-Oct-2018.)
|
| ⊢
(∀!𝑥(𝜑 → 𝜓) ↔ (∀𝑥(𝜑 → 𝜓) ∧ ∃𝑥𝜑)) |
| |
| Definition | df-alsc 16802 |
Define "all some" applied to a class, which means 𝜑 is true
for all
𝑥 in 𝐴 and there is at least one 𝑥 in
𝐴.
(Contributed by
David A. Wheeler, 20-Oct-2018.)
|
| ⊢
(∀!𝑥 ∈
𝐴𝜑 ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∃𝑥 𝑥 ∈ 𝐴)) |
| |
| Theorem | alsconv 16803 |
There is an equivalence between the two "all some" forms.
(Contributed by
David A. Wheeler, 22-Oct-2018.)
|
| ⊢
(∀!𝑥(𝑥 ∈ 𝐴 → 𝜑) ↔ ∀!𝑥 ∈ 𝐴𝜑) |
| |
| Theorem | alsi1d 16804 |
Deduction rule: Given "all some" applied to a top-level inference,
you
can extract the "for all" part. (Contributed by David A.
Wheeler,
20-Oct-2018.)
|
| ⊢ (𝜑 → ∀!𝑥(𝜓 → 𝜒)) ⇒ ⊢ (𝜑 → ∀𝑥(𝜓 → 𝜒)) |
| |
| Theorem | alsi2d 16805 |
Deduction rule: Given "all some" applied to a top-level inference,
you
can extract the "exists" part. (Contributed by David A.
Wheeler,
20-Oct-2018.)
|
| ⊢ (𝜑 → ∀!𝑥(𝜓 → 𝜒)) ⇒ ⊢ (𝜑 → ∃𝑥𝜓) |
| |
| Theorem | alsc1d 16806 |
Deduction rule: Given "all some" applied to a class, you can extract
the "for all" part. (Contributed by David A. Wheeler,
20-Oct-2018.)
|
| ⊢ (𝜑 → ∀!𝑥 ∈ 𝐴𝜓) ⇒ ⊢ (𝜑 → ∀𝑥 ∈ 𝐴 𝜓) |
| |
| Theorem | alsc2d 16807 |
Deduction rule: Given "all some" applied to a class, you can extract
the "there exists" part. (Contributed by David A. Wheeler,
20-Oct-2018.)
|
| ⊢ (𝜑 → ∀!𝑥 ∈ 𝐴𝜓) ⇒ ⊢ (𝜑 → ∃𝑥 𝑥 ∈ 𝐴) |