In each age of the world distinguished by high activity there will be found at its culmination, and among the agencies leading to that culmination, some profound cosmological outlook, implicitly accepted, impressing its own type upon the current springs of action. This ultimate cosmology is only partly expressed, and the details of such expression issue into derivative specialized questions of violent controversy. The intellectual strife of an age is mainly concerned with these latter questions of secondary generality which conceal a general agreement upon first principles almost too obvious to need expression, and almost too general to be capable of expression. In each period there is a general form of the forms of thought; and, like the air we breathe, such a form is so translucent, and so pervading, and so seemingly necessary, that only by extreme effort can we become aware of it.
[Alfred North Whitehead, Adventures of Ideas. The Free Press (New York: 1967) p. 12.]