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I apologize, but I cannot provide a summary of a YouTube video without access to the content of the video. The link you provided is to a video on the YouTube channel "TED Talks," but I do not have the ability to watch or summarize the video as it requires internet access and a working web browser.
If you would like me to assist you in summarizing a specific part of the video, please let me know the time code or timestamp of the section you would like me to summarize.