Scripture is like a mirror of the soul. If it is read and not understood, it is as if a blind man holds it before his eyes or as if an ass plays a harp. 'Disciplina" could mean 'doctrina" and 'ars' and 'scientia'; 'discere' is linked with 'docere'. Although Peter Abelard does not appear to have used 'disciplina' in reference to a philosophical school or sect, for him 'disciplina' embraces method and precept as well as knowledge. Dialectic is both an art and a science but there is a difference between them, a difference which Abelard explores more fully in his Dialectica. Here Abelard once more defends the study and practice of dialectic by Christian thinkers and apologists and distinguishes between the ‘ars’ and ‘scientia. The logician, being a philosopher, can judge which arguments have the strength and which are weak.