論理

ronri.xyz

Point. Line. Plane. Logic as visual form.

LINIE

Logical Connectives

→

Implication

∧

And

∨

Or

¬

Not

↔

Biconditional

⊢

Turnstile

FLÄCHE

Arguments as Compositions

Modus Ponens

1. P → Q premise

2. P premise

∴ Q MP 1,2

P → Q

TTT

TFF

FTT

FFT

Contrapositive

P → Q ≡ ¬Q → ¬P

Hypothetical Syllogism

1. P → Q

2. Q → R

∴ P → R

KOMPOSITION

The Complete Logic

∀x(P(x) → Q(x)) ∧ P(a) ⊢ Q(a)