Listening to President Obama's elegant eulogy for Ted Kennedy on Saturday, I was struck by the differences between the two great orators, and also by the epic struggle Obama is facing right now in trying to advance their shared ideals. 

Kennedy was a lion. It was his great roar of passion that so often won over constituents and colleagues. 

Obama is a famously cool cat. While sharing many of Kennedy's political goals, his oratory is built on reason and clarity. He employs low-voltage words that aim to stimulate our frontal cortex, the part of our brain that considers, compares, and calculates what's best for our future. Obama obviously believes deeply in the power of this rational oratory, and with the help of his extraordinary chief speechwriter, Jon Favreau, has turned precision and clarity into an art form.

From his Kennedy eulogy:

We cannot know for certain how long we have here. We cannot foresee the trials or misfortunes that will test us along the way. We cannot know God's plan for us. What we can do is to live out our lives as best we can with purpose, and love, and joy. We can use each day to show those who are closest to us how much we care about them, and treat others with the kindness and respect that we wish for ourselves. We can learn from our mistakes and grow from our failures. And we can strive at all costs to make a better world, so that someday, if we are blessed with the chance to look back on our time here, we can know that we spent it well; that we made a difference; that our fleeting presence had a lasting impact on the lives of other human beings.

While he was seen by his fiercest critics as a partisan lightning rod, that is not the prism through which Ted Kennedy saw the world, nor was it the prism through which his colleagues saw him. He was a product of an age when the joy and nobility of politics prevented differences of party and philosophy from becoming barriers to cooperation and mutual respect -- a time when adversaries still saw each other as patriots.