Frequent changes of home meant he was educated in London, Jersey, and Brittany and finally at Dr Charles Burney's school in Greenwich.
He conducted experiments on the reflexes and the nervous system of living animals, especially frogs, using ether and chloroform out of consideration for their pain.
[3] He became friends with Leigh Hunt, and through him he entered London literary society and met John Stuart Mill, Thomas Carlyle and Charles Dickens.
[5] Between 1842 and 1848, Lewes and his wife had four sons together, Charles Lee, Thornton Arnott, Herbert Arthur, and St Vincent Arthy.
Because Lewes was named on the birth certificate as the father of one of these children despite knowing this to be false, he was considered complicit in adultery and was not able to divorce Agnes.
[6] From 1840 to 1850, Lewes supported himself by contributing to quarterly and other reviews, articles discussing a wide range of subjects, often imperfect but revealing acute critical judgment enlightened by philosophic study.
[2] In 1845–46, Lewes published The Biographical History of Philosophy, an attempt to depict the life of philosophers as an ever-renewed fruitless labour to attain the unattainable.
In 1847–48, he published two novels – Ranthorpe, and Rose, Blanche and Violet – which, though displaying considerable skill in plot, construction, and characterisation, have taken no permanent place in literature.
Lewes's versatility, and his combination of scientific with literary tastes, eminently fitted him to appreciate the wide-ranging activity of the German poet.
[2][8] In 1865, when The Fortnightly Review began publication, Lewes became its editor, but he retained the post for less than two years, when he was succeeded by John Morley.
Yet he did not at any time give unqualified assent to Comte's teachings, and with wider reading and reflection his mind moved further away from the positivist stance.
His sudden death cut short the work, yet it is complete enough to allow a judgment on the author's matured conceptions on biological, psychological and metaphysical problems.
He was still positivist enough to pronounce all inquiry into the ultimate nature of things fruitless: what matter, form, and spirit are in themselves is a futile question that belongs to the sterile region of "metempirics".
Thus sensibility belongs as much to the lower centres of the spinal cord as to the brain, the former, more elementary, form contributing to the subconscious region of mental life, while the higher functions of the nervous system, which make up our conscious mental life, are more complex modifications of this fundamental property of nerve substance.
Every mental state is regarded as compounded of three factors in different proportions – sensible affection, logical grouping and motor impulse.
His biological experience prepared him to view mind as a complex unity of which the highest processes are identical with and evolved out of the lower.
The exceptional rapidity and versatility of his intelligence seems to account at once for the freshness in his way of envisaging the subject matter of philosophy and psychology, and for the want of satisfactory elaboration and of systematic coordination.
[10] Lewes died on the 30 November 1878[2] and is buried on the eastern side of Highgate Cemetery, beside the grave of his common-law wife Mary Ann Evans, penname George Eliot.