The claim is also sometimes made that science is as arbitrary or irrational as all other claims to knowledge, or that reason itself is an illusion. As Ethan Allen said Those who invalidate reason ought seriously to consider whether they argue against reason with or without reason; if with reason, then they establish the principle that they are labouring to dethrone. If they argue without reason, which they must do, in order to be consistent with themselves, they are out of reach of rational conviction, nor do they deserve a rational argument.
Carl SaganI would be very ashamed of my civilization if we did not try to find out if there is life in outer space.
Carl SaganThe fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses.
Carl SaganWidespread intellectual and moral docility may be convenient for leaders in the short term, but it is suicidal for nations in the long term. One of the criteria for national leadership should therefore be a talent for understanding, encouraging, and making constructive use of vigorous criticism.
Carl Sagan