Should you wish to make sure that your birthday will be celebrated three hundred years hence, your best course is undoubtedly to keep a diary. Only first be certain that you have the courage to lock your genius in a private book and the humour to gloat over a fame that will be yours only in the grave. For the good diarist writes either for himself alone or for a posterity so distant that it can safely hear every secret and justly weigh every motive. For such an audience there is need neither of affectation nor of restraint. Sincerity is what they ask, detail, volume; skill with the pen comes in conveniently, but brilliance is not necessary; genius is a hindrance even; and should you know your business and do it manfully, posterity will let you off mixing with great men, reporting famous affairs, or having lain with the first ladies in the land.