If an image is a mental picture that is constructed, then it's fair to say that many of Dr. King's images in the "I Have a Dream" speech are a reflection of a world of what can be as opposed to what is. One such image would be when Dr. King speaks of a journey towards Civil Rights. Dr. King uses the image of the "walk" to help communicate this: "We cannot walk alone. And as we walk, we must make the pledge that we shall always march ahead. We cannot turn back." Dr. King's image of the walk helps to communicate how Civil Rights and racial equality are a journey, a voyage or quest that only the strongest must be committed to undertaking. It is a journey that must be continued into the future to ensure its realization.
Dr. King employs the images of nature in his speech. In doing so, he is able to communicate how Civil Rights is a natural entitlement that people of color merit. It is a means through which Dr. King transforms the issue of Civil Rights from a political one to a moral one. When Dr. King uses imagery such as "until justice rolls down like waters, and righteousness like a mighty stream" and "Let us not wallow in the valley of despair," it helps to communicate the natural condition of Civil Rights, something that links it to a larger configuration. In using the natural images, Dr. King is able to emphasize how Civil Rights need to be realized as a natural consequence in both the present and the future.
Finally, one of the most poignant images of the speech is when Dr. King invokes the "table of brotherhood." Evoking images of the communion and meal where all are welcome, Dr. King uses the image of coming together to emphasize what his dream looks like: "I have a dream that one day on the red hills of Georgia, the sons of former slaves and the sons of former slave owners will be able to sit down together at the table of brotherhood." The "table of brotherhood" image indicates a vision for the future, one that justifies why the dream is worthy of sacrifice.