This book aims at applying the principles of Scholasticism to the solution of the problems raised by a critical inquiry into the validity of knowledge and the grounds of certitude. It does not purport to be in any sense a history of theories of knowledge, or to supply anything like an adequate bibliography of works on the subject. It is primarily a text-book for the use of university students in philosophy, though it is hoped that a perusal of it may be found helpful to all who desire a closer ...