4 ms·
Off topic: DeMorgan's law > the negation of a disjunction is the conjunction of the negations As a non-English speaker I hated this definition until someone t
by srikz 8y ago
Off topic: DeMorgan's law
> the negation of a disjunction is the conjunction of the negations
As a non-English speaker I hated this definition until someone told me to remember
> 'break the line, change the sign'.
This is of course referring the representation in boolean algebra, where, NOT(A AND B) is represented with a single long horizontal line on top of (A AND B). This becomes NOT(A) OR NOT(B), i.e., Ā | B̄ according to DeMorgan's law.
- giornogiovanna 8y agoDe Morgan's law is just "not all true <=> at least one's false". I'm not sure why people complicate it beyond that.
- blattimwind 8y agoIn university I had a course (curse?) called "logic in formal systems" (or something like that); I doubt many using only the course's materials truly understood the logic principles demonstrated there. Coincidentally, the course insisted on using ∧, ∨, ¬ etc., while another course also dabbling in a lot of logic using natural symbols was far better in terms of presentation and explanations. (To this day I have to look ∧, ∨, con- and disjunction up to be sure which is which).
- Izkata 8y ago> To this day I have to look ∧, ∨, con- and disjunction up to be sure which is which Tip: ∧ is shaped like the "A" in "And". Hopefully others know tricks for the other symbols.
- blattimwind 8y ago> Tip: ∧ is shaped like the "A" in "And". Meanwhile ∨ is shaped like the "U" in "Und" ...