And as the labor is impressive, so is the patience. The man was naturally nervous, restless, eager. He wanted results, like the rest of us. Yet after he had conceived a theory which he thought destined to subvert the whole realm of science, he waited twenty years for the thorough observation and testing necessary to put the theory into even tentative form. Of all the great scientific qualities perhaps patience is the most essential and the most difficult, and surely patience never had a more supreme exemplar than Charles Darwin. Sometimes even his enduring persistence is temporarily shaken: ‘My cirripedial task is an eternal one; I make no perceptible progress. I am sure that they belong to the hour-hand, and I groan under my task.’[41] But though he may groan, he never yields. As his son admirably says of him: ‘He used almost to apologize for his patience, saying that he could not bear to be beaten, as if this were rather a sign of weakness on his part.... Perseverance seems hardly to express his almost fierce desire to force the truth to reveal itself. He often said that it was important that a man should know the right point at which to give up an inquiry. And I think it was his tendency to pass this point that inclined him to apologize for his perseverance, and gave the air of doggedness to his work.’[42] The intensity of such patience is best appreciated by those who all their lives have scamped and hurried and slighted and touched a thousand things without ever going to the bottom of a single one. III