Diary of John Adams, volume 1
The first Maxim of worldly Wisdom, constant Dissimulation, may be good or evil as it is interpreted. If it means only a constant Concealment from others of such of our Sentiments, Actions, Desires, and Resolutions, as others have not a Right to know, it is not only lawful but commendable—because when these are once divulged, our Enemies may avail themselves of the Knowledge of them, to our Damage, Danger and Confusion. So that some Things which ought to be communicated to some of our Friends, that they may improve them to our Profit or Honour or Pleasure, should be concealed from our Enemies, and from indiscreet friends, least they should be turned to our Loss, Disgrace or Mortification. I am under no moral or other Obligation to publish to the World, how much my Expences or my Incomes amount to yearly. There are Times when and Persons to whom, I am not obliged to tell what are my Principles and Opinions in Politicks or Religion.
There are Persons whom in my Heart I despize; others I abhor. Yet I am not obliged to inform the one of my Contempt, nor the other of my Detestation. This Kind of Dissimulation, which is no more than Concealment, Secrecy, and Reserve, or in other Words, Prudence and Discretion, is a necessary Branch of Wisdom, and so far from being immoral and unlawfull, that
Yet even this must be understood with certain Limitations, for there are Times, when the Cause of Religion, of Government, of Liberty, the Interest of the present Age and of Posterity, render it a necessary Duty for a Man to make known his Sentiments and Intentions boldly and publickly. So that it is difficult to establish any certain Rule, to determine what Things a Man may and what he may not lawfully conceal, and when. But it is no doubt clear, that there are many Things which may lawfully be concealed from many Persons at certain Times; and on the other Hand there are Things, which at certain Times it becomes mean and selfish, base, and wicked to conceal from some Persons.