Meteorologies.
                 {15.  Researches about Animals.
                 {16.  On Parts of Animals.
                 {17.  On Locomotion of Animals.
                 {18.  On Generation of Animals. 
III.  Natural {19.  On the Soul. 
Philosophy. {20.  Appendices to the work “On the Soul.”
                 { (a) On Sense and Sensible Things.
                 { (b) On Memory and Recollection.
                 { (c) On Sleep and Waking.
                 { (d) On Dreams and Prophesying in Sleep.
                 { (e) On Longevity and Shortlivedness.
                 { (f) On Youth and Old Age.
                 { (g) On Life and Death.
                 { (g) On Respiration.

IV.  Rational {21.  Metaphysics. 
Philosophy. {

This encyclopedic collection became accessible in Latin translations only by slow degrees.  Abelard knew only the first two (possibly also the third and fourth) works of the Organon.  John of Salisbury, in the next generation, was familiar with the six treatises of the Organon, but apparently not with the others.  Little seems to have been added to these until the beginning of the thirteenth century, when the Ethics, the Physics, and the Metaphysics were mentioned at Paris,—­the last two as forbidden works.  The great era of translation seems to have been between 1200 and 1270, when both Arabic-Latin and Greek-Latin versions were made of most of the remaining treatises.  The recovery of Aristotle thus occupied more than a century and a half.  During that period the intellectual life of western Europe was stimulated by the influx of hitherto unknown works of that philosopher, and weighty additions were made to the list of available studies.

As usual, the world of scholars and the universities were slow to recognize the worth of the new studies.  This was due partly to the natural conservatism of teachers, and partly to the fear of ecclesiastical authorities that the study of Aristotle would give rise to heresies.  Thus in the documents of the time we meet, on the one hand, vigorous arguments by progressive scholars in favor of Aristotle, and on the other, university regulations prescribing what books shall or shall not be studied.

The attitude of Abelard toward Aristotle has already been cited (see p. 19).

His pupil, John of Salisbury, devotes a considerable portion of the Metalogicus to a discussion of the utility of the various portions of the Organon and to the defense of Aristotle, as is shown by the titles of various chapters of that work.  It is important to remember that he is advocating the study of the newly translated books, as well as those already known: 

     That Logic, because it seeks the truth, takes the lead in all
     Philosophy.

     On the usefulness of the Categories and their appliances.