We were told in one lecture that it was possible to immunize against diphtheria and tetanus by the use of chemically treated toxins, or toxoids. And … - Jonas Salk

Nothing happens quite by chance. It's a question of accretion of information and experience … it's just chance that I happened to be here at this particular time when there was available and at my disposal the great experience of all the investigators who plodded along for a number of years.

Some people are constructive, if you like. Others are destructive. It's this diversity in humankind that results in some making positive contributions and some negative contributions. It's necessary to have enough to make positive contributions to overcome the problems of each age.

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.