i also think the “etymology” of the boolean symbols is very helpful in remembering which is which. in lattice theory, their use was inspired by similar notation in set theory. so, A ∨ B is like A ∪ B, while A ∧ B is like A ∩ B.
generally, A ∨ B is “the smallest thing that’s greater than or equal to both A and B”, while A ∧ B is “the biggest thing that’s less than or equal to both A and B”. similarly to how A ∪ B is “the smallest set that contains both A and B”, while A ∩ B is “the largest set that’s contained in both A and B”. you can also take things a step further by saying that in the context of sets, A ≤ B means A ⊆ B. doing this means that A ∨ B = A ∪ B, while A ∧ B = A ∩ B. and from this perspective, the “sharp-edged” symbols (<, ∧, ∨) are just a generalization of their “curvy” counterparts (⊂, ∩, ∪).
in the context of boolean algebra, you can set False < True, which at first may seem a bit arbitrary, but it agrees with the convention the that False = 0 and True = 1, and it also makes A ∨ B and A ∧ B have the same meanings as described above.
for some reason to remember ∩ and ∪ when I first learned it in school I visualized a mirrored symbol on top. the ∩ looked like a X which represented an intersection, while ∪ looked like an O which represented a whole. for English ∪ already looks like a U which can be thought of as short for union. that would’ve been easier.
ooh the mirror trick is quite handy. i don’t think i’ve heard that one before. i’ll keep that one in my back pocket in case i ever need it some day. i can’t remember exactly how i learned what they meant, but i think it was probably u for union and n for ntersection.
i also think the “etymology” of the boolean symbols is very helpful in remembering which is which. in lattice theory, their use was inspired by similar notation in set theory. so,
A ∨ Bis likeA ∪ B, whileA ∧ Bis likeA ∩ B.generally,
A ∨ Bis “the smallest thing that’s greater than or equal to both A and B”, whileA ∧ Bis “the biggest thing that’s less than or equal to both A and B”. similarly to howA ∪ Bis “the smallest set that contains both A and B”, whileA ∩ Bis “the largest set that’s contained in both A and B”. you can also take things a step further by saying that in the context of sets,A ≤ BmeansA ⊆ B. doing this means thatA ∨ B = A ∪ B, whileA ∧ B = A ∩ B. and from this perspective, the “sharp-edged” symbols (<,∧,∨) are just a generalization of their “curvy” counterparts (⊂,∩,∪).in the context of boolean algebra, you can set
False < True, which at first may seem a bit arbitrary, but it agrees with the convention the thatFalse = 0andTrue = 1, and it also makesA ∨ BandA ∧ Bhave the same meanings as described above.for some reason to remember ∩ and ∪ when I first learned it in school I visualized a mirrored symbol on top. the ∩ looked like a X which represented an intersection, while ∪ looked like an O which represented a whole. for English ∪ already looks like a U which can be thought of as short for union. that would’ve been easier.
ooh the mirror trick is quite handy. i don’t think i’ve heard that one before. i’ll keep that one in my back pocket in case i ever need it some day. i can’t remember exactly how i learned what they meant, but i think it was probably u for union and n for ntersection.