By that logic, because the diffraction limit of the human eye is orders of magnitude away from being able to image a star, we cannot see stars.

For resolution, the question might be better stated: Can you tell the difference between

   a)        **

and

   b)        * *

The two images have the same aggregate intensity, but different morphology.

The ancients played the same game as a vision test with stars:

http://en.wikipedia.org/wiki/Mizar_and_Alcor