Joseph Addison, The Spectator
, no. 162 (Tuesday, September 5, 1711):
Nothing that is not a real Crime makes a Man appear so contemptible and little in the Eyes of the World as Inconstancy, especially when it regards Religion or Party. In either of these Cases, tho' a Man perhaps does but his Duty in changing his Side, he not only makes himself hated by those he left, but is seldom heartily esteemed by those he comes over to.
In these great Articles of Life, therefore, a Man's Conviction ought to be very strong, and if possible so well timed that worldly Advantages may seem to have no Share in it, or Mankind will be ill natured enough to think he does not change Sides out of Principle, but either out of Levity of Temper or Prospects of Interest.