The most powerful drive in the ascent of man is his pleasure in his own skill. He loves to do what he does well. And having done it well, he loves to do it better.

No science is immune to the infection of politics and the corruption of power.

Dissent is the mark of freedom, as originality is the mark of independence of mind. … No one can be a scientist … if he does not have independence of observation and of thought.

Science is a tribute to what we can know, although we are fallible.

The men who made the Industrial Revolution are usually pictured as hardfaced businessmen with no other motive than self-interest. That is certainly wrong. For one thing, many of them were inventors who had come into business that way.

[John] Dalton was a man of regular habits. For fifty-seven years he walked out of Manchester every day; he measured the rainfall, the temperature-a singularly monotonous enterprise in this climate. Of all that mass of data, nothing whatever came. But of the one searching, almost childlike question about the weights that enter the construction of these simple molecules-out of that came modern atomic theory. That is the essence of science: ask an impertinent question, and you are on the way to the pertinent answer.

Certainty ends inquiry.