{12. On the Heavens.
{13. On Generation and Destruction.
{14. 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