PROPORTION
in this painting is realistic.  The artist was trying to recreate a real life reproduction of the objects he painted. 

The size of the fruit in relation to the pitcher, bowl and plate lets the viewer know how big the objects really are.  For example, the plate is big enough to fit six pieces of fruit onto it.

In this painting the artist has exaggerated the proportion of the objects to one another to create a certain look to his painting.

For instance, a real pear would be smaller than the rocks on the ground, but the artist has made it as big as the sun.  The artist did this to draw attention to certain images within the painting.