unworkable

absurd futile impassable impractical unattainable unreasonable unthinkable useless

beyond contrary to reason cureless hardly possible hopeless hundred-to-one impervious impracticable inaccessible inconceivable inexecutable infeasible insurmountable irrealizable irreparable no-go no-win not a prayer out of the question preposterous too much unachievable uncorrectable unfeasible unimaginable unobtainable unrealizable unrecoverable visionary way-out

logical practical reasonable sensible

absurd illogical impossible impractical unattainable unusable useless

abstract chimerical idealistic improbable inapplicable inefficacious infeasible inoperable irrealizable ivory-tower no-go nonfunctional nonviable not a prayer otherworldly out of the question quixotic romantic speculative starry-eyed theoretical unbusinesslike unfeasible unnegotiable unreal unserviceable visionary wild won't fly

logical rational reasonable sensible