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The Giver, Jonas and Gabe all have pale eyes. This makes them very unusual in a society that valued conformity above anything else and that went to great lengths to enforce "Sameness" in all things. The significance of the eye color is not that it is pale, rahter than dark as are the eyes of the others in the community. The symbolic meaning of that difference in eye color relates to the difference in ability to perceive, see, and understand beyond the uniformity sensed by the others.
Jonas first became aware of his ability to "see beyond" when, for the briefest of moments, the apple changed appearance. The first time it happened, because it was a new experience, Jonas didn't know that what he was seeing was a color; he simply realized that something had changed. Without understanding what was happening or why, he began to be aware of other instances that involved the same experience of changed perception.
But when he looked out across the crowd, the sea of faces, the thing happened again. The thing that had happened with the apple. They changed. He blinked, and it was gone. His shoulder straightened slightly. Briefly he felt a tiny sliver of sureness for the first time.
Under the Giver's training, Jonas came to understand the impact of "sameness," the losses that it had brought to the community, and he developed his abilities to see beyond the superficially imposed limits of the community.
Our people made that choice, the choice to go to Sameness. Before my time, before the previous time, back and back and back. We relinquished color when we relinquished sunshine and did away with difference. We gained control of many things. But we had to let go of others.
The two people with pale eyes in, "The Giver" is Jonas and Gabriel.