Read it through once

Yet Mr. Dimmesdale would perhaps have seen this individual’s character more perfectly, if a certain morbidness, to which sick hearts are liable, had not rendered him suspicious of all mankind. Trusting no man as his friend, he could not recognize his enemy when the latter actually appeared. He therefore still kept up a familiar intercourse with him, daily receiving the old physician in his study; or visiting the laboratory, and, for recreation’s sake, watching the processes by which weeds were converted into drugs of potency.