For the other respondents, Mr. Siegel's point is that even the most brilliant of scientists are human, meaning that they are fallible, that all have feet of clay. Great scientists, once they have made their mark on history, have often forgotten the necessity of humility, and the need to drink deeply of the Pierian spring of knowledge, or not at all.
It is true that I am an avowed contrarian (the kind that Mr. Siegel warns about), but the statements he makes are from his vantage point upon the shoulders of giants. I wouldn't be so quick to disparage what he has to say.