“I was taught that the way of progress was neither swift nor easy.”

“To be content with life, or to live merrily, rather, all that is required is that we bestow on all things only a fleeting, superficial glance; the more thoughtful we become the more earnest we grow”

“We gain nothing by being with such as ourselves. We encourage one another in mediocrity. I am always longing to be with men more excellent than myself”

“Those who never have time do least”

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

“In science, we must be interested in things, not in persons”