It is clear that thought is not free if the profession of certain opinions makes it impossible to earn a living. Bertrand Russell
It is clear that every civilization undergoes a process of historical change. We can see that a civilization comes into existence, passes through a long experience, and eventually goes out of existence. Carroll Quigley
It is clear that economics, if it is to be a science at all, must be a mathematical science. William Stanley Jevons
But it is clear that the price of labour has no necessary connection with the price of food, since it depends entirely on the supply of labourers compared with the demand. David Ricardo
While it is clear that we need to make some adjustments to protect Social Security for the long term, it is disingenuous to say that the trust fund is facing a crisis. Carl Levin
It is clear that there is no classification of the Universe that is not arbitrary and full of conjectures. The reason for this is very simple: we do not know what kind of thing the universe is. Jorge Luis Borges