There's the assumption being made by the national security advisers to the Obama administration that the North Korean leadership is not suicidal, that they know they will be obliterated if they attacked the United States. But I would point that everything in South Korea and Japan is well within range of what they might want to do.
There can be no assumption that today's majority is 'right' and the Amish and others like them are 'wrong.' A way of life that is odd or even erratic but interferes with no rights or interests of others is not to be condemned because it is different.
If you look at the history of big obstacles in understanding our world, there's usually an intuitive assumption underlying them that's wrong.
I am just postmodern enough not to trust 'postmodern' as a description of our times, for it privileges the practices and intellectual formations of modernity. Calling this a postmodern age reproduces the modernist assumption that history must be policed by periods.
I never attempt to make money on the stock market. I buy on the assumption that they could close the market the next day and not reopen it for five years.