Henry More (; 12 October 1614 – 1 September 1687) was an English philosopher, Anglican priest, theologian, and poet, associated with the Cambridge Platonists. He sought to reconcile Platonism with Christian theology and responded critically to Cartesian philosophy. His metaphysical writings addressed the nature of spirit, matter, divine providence, and the soul, and he was a prominent voice in seventeenth-century religious and philosophical debates.
More rejected Cartesian dualism, arguing that spirit, like matter, must be extended in space. He coined the term fourth dimension and introduced the concept of essential spissitude to describe the spatial extension of immaterial substance. He also proposed the existence of a Spirit of Nature—an unconscious, incorporeal agent through which God sustained the order of the physical world. His metaphysics grounded his opposition to materialist atheism and emphasised the necessity of immaterial principles in explaining life and motion.
He opposed the Cartesian view that animals were mere machines, asserting instead that they possess immaterial but mortal souls. More regarded animals as part of divine providence and cited their usefulness to humans as evidence of design, while acknowledging the theological difficulty posed by predation and suffering.
His writings, in both Latin and English, spanned metaphysics, ethics, natural philosophy, and theology, and included poetry and prose. He influenced figures such as Lady Anne Conway, Joseph Glanvill, and John Norris, and was later cited by Ralph Waldo Emerson and Helena Blavatsky.
Henry More was born in Grantham, Lincolnshire on 12 October 1614. He was the seventh son of Alexander More, mayor of Grantham, and his wife Anne More (née Lacy). Although both parents were Calvinists, More later wrote that he "could never swallow that hard doctrine."
He was educated at The King's School, Grantham and at Eton College, before entering Christ's College, Cambridge in 1631, around the time that John Milton was departing. He received his BA in 1635 and his MA in 1639, and was shortly thereafter elected a fellow of his college, declining all other preferments. He declined the mastership of Christ's College in 1654, despite indications that he was the preferred candidate, and the position was instead offered to Ralph Cudworth. In 1675, More accepted a prebend at Gloucester Cathedral, but soon resigned it in favour of his friend Edward Fowler, who later became bishop of Gloucester.
Among More's students was Anne Finch, sister of Heneage Finch, who later became Lady Conway. At her estate at Ragley in Warwickshire, More spent a significant amount of time and composed several of his works. Lady Conway's spiritual interests influenced some of More's philosophical ideas, although she eventually joined the Quakers. She maintained friendships not only with More and William Penn, but also with figures such as Franciscus Mercurius van Helmont and Valentine Greatrakes, both associated with 17th-century mystical and thaumaturgical traditions. Ragley thus became a centre of spiritual and religious activity.
More died in Cambridge on 1 September 1687 and was buried in the chapel of Christ's College.
Henry More developed a metaphysical system influenced by Neoplatonism, while also engaging with aspects of the emerging mechanical philosophy of the seventeenth century. Although often associated with the Cambridge Platonists, his views diverged in several respects.
More rejected Calvinist predestinarianism and materialist atheism, maintaining that God was morally perfect and necessarily governed by absolute standards of goodness. He argued that moral truths were eternal and independent of divine will, in contrast to the voluntarist theology associated with Calvinism. On this basis, More held that God was obliged to create the best possible world—not for the benefit of humanity, but to manifest divine perfection.
More's philosophy included a dualistic distinction between body and spirit. He described matter as inert and passive, asserting that all motion and activity must originate in immaterial spirit. He extended this principle to all living beings, maintaining that life and movement required the presence of an immaterial, self-moving soul.
Although initially receptive to Cartesian thought, More later criticised its core principles. He rejected Descartes's identification of body with extension, arguing that immaterial substances were also extended. In More's view, to exist was to exist in space; therefore, even God, souls, and angels must possess spatial extension. He defined spirit not by the absence of extension but by its penetrability and indivisibility.
More rejected Cartesian dualism on the grounds that it was, in his view, more coherent to attribute matter and extension to the soul than to ascribe to an immaterial substance the capacity to move and be moved by the body. His reservations were not based on difficulties in explaining the interaction between material and immaterial substances, but rather on a philosophical position that regarded extension as a necessary condition for existence. As he wrote, "... it is plain that if a thing be at all it must be extended." On this basis, More argued that spirit must also be extended. This led him to propose the concept of a fourth dimension (a term he is credited with coining) in which spirit possesses extension—a property he termed essential spissitude—as part of his proposed resolution to the mind–body problem.
To account for natural phenomena he regarded as inadequately explained by mechanical laws—such as gravity, magnetism, and biological instincts—More proposed the existence of the Spirit of Nature. He described it as an incorporeal but extended substance that functioned as a secondary, unconscious cause in nature. Although distinct from God, it was considered a necessary emanation of divine power through which God maintained the order of the physical world.
More articulated a view of absolute space and time as real, immaterial entities. He described space as infinite, extended, and incorporeal, attributing to it qualities such as omnipresence and immutability. He considered space strong evidence for the reality of immaterial substance. Rejecting the Cartesian position that immaterial souls exist "nowhere" (nullibism), he maintained that all beings exist spatially. Time, likewise, was regarded as absolute and independent of perception. Both space and time were seen as emanative effects of divine presence.
More's metaphysical system presented matter as dependent on active, extended spirit. He engaged with contemporary debates in natural philosophy, theology, and metaphysics, and responded critically to aspects of Cartesianism.
Henry More rejected the Cartesian doctrine of animal automatism, maintaining instead that animals possess immaterial souls. While he denied that animal souls were immortal, he held that they were distinct from matter and capable of sensation and self-motion. This view was integral to his broader metaphysical system, which depended on a strict dualism between passive matter and active spirit. For More, denying souls to animals risked collapsing this distinction and opening the door to atheistic materialism.
More regarded animals as part of divine providence, often citing their usefulness to humans—as sources of food, labour, or companionship—as evidence of design. He also argued that even wild or dangerous animals served providential ends, such as testing human courage or contributing to the beauty and complexity of creation. However, the existence of predatory and harmful animals raised theological challenges, especially concerning the problem of evil. In response, More suggested that such creatures reflected the limitations of creation rather than flaws in the divine will.