Does science have all the answers?

Sam Harris, the atheist author, has an op-ed piece in the New York Times, Science is in the Details, arguing that Francis Collins is not a suitable choice to head the National Institute for Health in the U.S. because of Collins' Christian beliefs. I recommend reading the full article and wikipedia page on Harris. But, the essence of his argument seems to be that Collins has written “science offers no answers to the most pressing questions of human existence” and Harris concludes:

Must we really entrust the future of biomedical research in the United States to a man who sincerely believes that a scientific understanding of human nature is impossible?

Science has many answers but it does not have all the answers. Having someone head NIH who acknowledges this seems like a good thing to me. Particularly, when that person has already successfully led the largest research project that NIH ever embarked upon.