Viktor Emil Frankl (1905-1997) was an Austrian neurologist and psychiatrist as well as a Holocaust survivor, as well as the founder of logotherapy, a form of existential psychotherapy. His most famous book (which also describes his experiences in the Holocaust) is Man's Search for Meaning.
He states in the Preface to this 1969 book, "This book is the outcome of a series of lectures I was invited to give during the 1966 summer session ... The particular task assigned to me at that time was to explain the system that characterizes logotherapy. While it has often been pointed out ... that logotherapy ... has developed a proper psycherapeutic technique ... it also is the last psychotherapy that is conceptualized in a systematic way."
Here are some representative quotations from the book:
"(L)ogotherapy is based on the following three concepts: (1) the freedom of the will; (2) the will to meaning; and (3) the meaning of life."
"After all, it is not the function of logotherapy to give answers. Its actual function is that of a catalyst."
"It is true that we logotherapists are convinced, and if need be, persuade our patients, that there is a meaning to fultill. But we do not pretend to know WHAT the meaning is."
"I personally believe that philosophy is not a mere sublimation of sex but rather that sex often serves as a cheap escape from precisely those philosophical and existential problems which beset man."
"What matters in life is rather to achieve something."
"Logotherapy does not cross the boundary between psychotherapy and religion. But it leaves the door open to religion and it leaves it to the patient whether or not to pass the door."
"I would say that God is not dead but silent. Silent, however, he has been all along. The 'living' God has been a 'hidden' God all along."