Piggy’s glasses are symbolic for a number of reasons in Lord of the Flies. The spectacles represent the boys’ only means of obtaining fire through reflecting the sun’s rays, and fire itself is symbolic of survival and rescue. Jack snatches the glasses off Piggy’s face to create the fire, despite Piggy’s protestations, and his dependence upon them. Later, Jack punches Piggy which cause the glasses to fall, smashing one side. Piggy is now half-blind, a foreshadowing of later events in the book when Jack’s tribe steal the spectacles, leaving Piggy completely blind and vulnerable.
The glasses are also symbolic of Piggy’s character; his rational thinking and ability to see a solution to the boys’ predicament. Once the glasses are stolen, and Piggy cannot see, he is unable to further help Ralph to maintain civilisation.