The Talmud teaches us that he who takes a life destroys an entire world.

Fifty years ago today, a world was destroyed. The assassination of President John F. Kennedy changed the world in ways we can never know, because history does not allow for peeks at what could have been.

All we have is the world that is, and that world, sad to say, is not a pleasant one. Even here, in America, the atmosphere is chilly, as we become ever more polarized politically and philosophically.

President Kennedy dreamed of a better world than what we have, and of a better America. He and his late brother Robert F. Kennedy, who also was assassinated a little less than five years later, often quoted George Bernard Shaw. “Some men see things as they are and ask why. I dream things that never were and ask why not.”

John F. Kennedy did not have a chance to amass a great record of achievements in his not quite three years in office. He had little time to try to change the world, but he inspired a generation. He gave voice to our hopes when he painted a vision of what could be.

As our nation mourns his death today and in the coming days, let us recall words he spoke then; words that are more relevant now than ever.

“Let us not seek the Republican answer or the Democratic answer, but the right answer,” he said. “Let us not seek to fix the blame for the past. Let us accept our own responsibility for the future.”

Perhaps the best way for all of us to honor his memory is not in revisiting Camelot, or rehashing conspiracy theories, but in dreaming things that never were, asking why not, and then turning those dreams into reality.