Our greatest responsibility is to be good ancestors. - Jonas Salk

I judge things from an evolutionary perspective — "How does this serve and contribute to the process of our own evolution?" — rather than think of good and evil in moral terms. I see the triumph of good over evil as a manifestation of the error-correcting process of evolution.

I look upon ourselves as partners in all of this, and that each of us contributes and does what he can do best. And so I see not a top rung and a bottom rung — I see all this horizontally — and I see this as part of a matrix. And I see every human being as having a purpose, a destiny, if you like. And what my hope is that we can find some way to fulfill the biological potential, if you like — the destiny that exists in each of us — and find ways and means to provide such opportunities for everyone. Now at the moment the world is suffering from large numbers of people who have no purpose in life — for whom there is no opportunity — and that's sad.

Reply when questioned on the safety of the polio vaccine he developed:

It is safe, and you can't get safer than safe.