'Irrational' in this context doesn't mean 'bad' - simply an alternative to a 'rational' philosophy which sought to ground all knowledge in thought. The existentialist philosophers dealt with in Barrette's book all, to some degree, see knowledge as grounded in experience.
Irrational Man subtitled "A Study In Existential Philosophy" basically is a important book written by William Barrette and was published in the year 1958 which served to initiate existentialism to the English speaking world.
The book has a total of four parts, in the third part which is known as The Existentialists, the four chief philosophers, Kierkegaard, Neitzsche, Heidegger and Sarte have been named, each of them explaining their primary thoughts and terminology on irrational philosophy. The thoughts of each philosopher offer a road map for people who are looking for principal works of each, which can be intense with exclusive terminology.
Friedrich Wilhelm Nietzsche was well known Prussian-born philosopher. He started his career as philologist and created evaluation of religion, principles, modern culture, values and science.
There is no such thing as irrational philosophy. However, philosophers such as Nietzsche were the exponents of a branch of philosophy which we now know as irrational epistemology. The term epistemology is defined as the study of knowledge and how it is achieved. An irrational epistemology is, therefore, defined as an irrational concept which destroys rational philosophy. It prevents the ability of the mind to function in a proper and rational manner, thereby making it extremely difficult or virtually impossible to get the other parts of the philosophy right.
A proper epistemology helps us gain valid understanding of the world, identify correct ideas and as it is based purely on logical reasoning, it is one of the means by which all human beings gain knowledge. On the other hand, an irrational epistemology hampers our ability to gain a valid understanding of the world. Irrational epistemology prevents us from identifying correct ideas and is irrational and inconsistent.
