sentient v. sapient

sentient: responsive to or conscious of sense impressions <sentient beings>  sapient: possessing or expressing great sagacitysagacious: a ) of keen and farsighted penetration and judgment: discerning <sagacious judge of character>; b) caused by or indicating acute discernment <sagacious purchase of stock>— Webster's Dictionary One could say that a sentient being responds to sense impressions, and a sapient being is capable of reason.