This book was written in 1968, and defended as a doctoral dissertation before the Philosophical Faculty at the University of Fribourg (Switzerland) in 1969. It treats of the systematic views of Hegel which led him to give to the princi ple of non-contradiction, the principle of double negation, and the principle of excluded middle, meanings which are difficult to understand. The reader will look in vain for the philosophical position of the author. A few words about the intentions which motivated the author to study and clarify Hegel's thought are therefore not out of place. In the early...