Gatsby throughout the whole novel was focused on one dream ,the dream he wanted was Daisy and her love. He thought that he would be able to conceive her love once more if he had possessed in the past, if he had shown her now that he could take care of her like he could not before.
"I thought of Gatsby‘s wonder when he first picked out the green light at the end of Daisy‘s dock. He had come a long way to this blue lawn, and his dream must have seemed so close that he could barely fail to grasp it. He did not know that it was already behind him, somewhere back in that vast obscurity beyond the city, where the dark fields of the republic rolled on under the night" (180, 182).
Through this we are able to see the "light" at the end of the dock. The light