A working list (incomplete) of things that are always in pairs (some paradoxically: pair of underwear?), (others controversially: male/female?) to be used later for inspiration in noding fiction on the theme of "Always in pairs". Favorites: entangled particles, soulmates, conscious/subconscious, jokers (poker deck), twins.
socks
shoes
gloves
twins
day/night
left/right
east/west
north/south
male/female
oxygen atoms
pants? (
pair of pants)
underwear (pair of)
soulmates
entangled particles
seed leaves of
dicotyledons
conscious/
subconscious
scissors
urban/rural
tin snips
jokers (poker deck)
jacks or better
eyes
ears
hands,
arms, legs, etc.
glasses
peanut butter and jelly
headphones
Feel free to suggest additional "always in pairs" candidates by /msg; I know I have missed many!