discern

verb4

1. •
   To detect with the senses, especially with the eyes.

   • Meanwhile the brig had altered her tack, and was moving slowly to the east. Three hours later and the keenest eye could not have discerned her top-sails above the horizon. — 1875
2. •
   To perceive, recognize, or comprehend with the mind; to descry.
3. •
   To distinguish something as being different from something else; to differentiate or discriminate.

   • He was too young to discern right from wrong.
4. •
   To perceive differences.