He later realized that he was far from being an ideal student. He was frustrated with the undergraduate system then. Nevertheless, he kept studying in his own way and read a lot, including the great works of Descartes and Hobbes. The writings of Descartes had awakened in him the interest in philosophy. His friendship with Robert Boyle led to an arousal in enthusiasm for the natural sciences. He thus became a medical student and eventually served as a physician to Lord Ashley, and eventually the Earl of Shaftesbury. This association with the brilliant Shaftesbury was good enough to influence Locke's life. He got what Hobbes did not manage to attain, which was a direct experience of all practical affairs, including political affairs. He held the weighty post of secretary to the Council of Trade and Plantations, of which Shaftesbury was president. He found his political works too taxing; he could not cope up with it. So, he left England in 1675 and spent around four years travelling all over France. After that, he returned to England and rejoined Shaftesbury for a brief time, only to realize that Oxford was better for his overall health than the stressful presence of his patron which was pressurizing and dangerously unstable too. There was a lot of controversy regarding his eventual decision of not returning to England by fleeing to Holland, in spite of a pardon offered to him, until the downfall of the Stuarts.
He got himself involved in Whig politics, where he helped plan William of Orange's expedition to England. All this got him a lot of experience, practically, it somehow made him sharper. It stimulated by the intellectual life of the Dutch, he made time to complete his studies. From the years 1689-1693, he released most of his works. Starting with 'Letter Concerning Toleration', which was followed by - 'Essay Concerning Human Understanding', 'Treatises on Civil Government', 'Second Letter on Toleration', 'Third Letter on Toleration' and 'Some Thoughts Concerning Education'.
