Who is Fries from The Logic of Scientific Discovery and what is their importance?

German philosopher, Fries, stated that if scientific statements are not to be accepted dogmatically, they must be justified by reasoned argument leading to a "predilection for proofs." Faced with the trilemma of infinite regress, dogmatism or psychologism, he embraces psychologism in his adherence to the value of immediate knowledge gained from the sense-experience. This experience is then mediated through symbols of language into scientific statements.