Certein bodies... become luminous when heated. Their luminosity disappears after some time, but the capacity of becoming luminous afresh through heat is restored to them by the action of a spark, and also by the action of radium.

There are sadistic scientists who hurry to hunt down errors instead of establishing the truth.

After all, science is essentially international, and it is only through lack of the historical sense that national qualities have been attributed to it.

Life is not easy for any of us. But what of that? We must have perseverance and above all confidence in ourselves.

Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.

Each of us must work for his own improvement, and at the same time share a general responsibility for all humanity.

Now is the time to understand more, so we fear less.