The Olive Tree

The Olive Tree is related to Athena and symbolises Divine wisdom. Because she was born from the Head of Zeus, she is related to the intelligible nature. The olive has a white part that is raised upward in the Summer and downwards in the Winter and is therefore similar to the movement of the soul through the two entrances, and symbolises the alternation between light and dark. It symbolises peace  and victory as the  fruits of labour in the Olympiad of the soul: "Thus, too, the world is governed by an intellectual nature, and is conducted by a wisdom eternal and ever-flourishing; by which the rewards of victory are conferred on the conquerors in the athletic race of life, as the reward of severe toil and patient perseverance" (17)
"For in summer the white leaves of the olive tend upwards, but in winter the whiter leaves are bent downward. On this account also in prayers and supplications, men extend the branches of an olive, nominating from this that they shall exchange the sorrowful darkness of danger for the fair light of security and peace. The olive, therefore being naturally ever-flourishing, bears fruit which is the auxiliary of labour (by being its reward , it is sacred to Minerva; supplies the victors in athletic labours with crowns and affords a friendly branch to the suppliant petitioner".(15)

 In this cave all things must be deposited in a process to purify the passions.  According to Plato in the Timaeus, Phorcys represents material nature. It is related that Numenius gives a general interpretation of the Odyssey: "On this account, too, a seat under the olive is proper to Ulysses, as to one who implores divinity and would appease his natal daemon with a suppliant branch. For it will not be simply, and in a concise way, possible for anyone to be liberated from this sensible life, who blinds this daemon, and renders his energies inefficacious; but he who dares to do this, will be pursued by the anger (note 25) of the marine and material Gods, whom it is first requisite to appease by sacrifices, labours, and patient endurance; at one time, indeed, contending with the passions, and at another employing enchantments and deceptions, and by these, transforming himself in an all-various manner; in order that, being at length divested of the torn garments (by which his true person was concealed) he may recover the ruined empire of his soul. Nor will he even then be liberated from labours; but this will be effected when he has entirely passed over the raging sea, and, though still living, becomes so ignorant of marine and material works (through deep attention to intelligible concern) as to mistake an oar for a corn-van" (17)