invalid

baseless false inoperative irrational null unfounded unreasonable unscientific unsound untrue

bad void wrong

fallacious ill-founded illogical mad not binding not working nugatory null and void reasonless sophistic unreasoned

honest logical reasonable sensible sound true valid

OK good right

worthwhile worthy

infirm sickly

ailing debilitated down frail ill peaked sick

bedridden below par feeble laid low on the sick list out of action poorly run down weak weakened

healthy strong well

sound worthy

consumptive convalescent incurable patient shut-in sufferer