Differing Views Of Motion: Aristotle And Lucretius

Differing Views of Motion: Aristotle and Lucretius

Throughout history, scientists and philosophers have tried to use various concepts such as motion to explain order and variety in the world. Two such philosophers are Aristotle and Lucretius. Both philosophers had differing views of the natural world, particularly the order and variety within it, but both philosophers use fundamental concepts of motion to underpin and account for their views.

In Chapter 8 of On the Heavens, Aristotle details his concept of motion while reasoning that there is only one world. Aristotle was a proponent of the Geocentric Model of Planetary movements, and he proposed that the Earth was the fixed centre of the Universe and all other planets and the sun were in orbit around it (Campbell and Campbell 2016). He also believed that the world consisted of four elements: earth (heaviest), water, air, and fire (lightest) (Campbell and Campbell 2016). Aristotle viewed ‘lightness’ as the motion of moving away from the centre, such as smoke moving towards the sky, and ‘heaviness’ was the motion of moving toward the centre, like a rock dropping down to the earth (Campbell and Campbell 2016). Aristotle also believed that the Earth was unique and has always existed. Throughout On the Heavens, Aristotle uses his concept of motion to account for his views on the natural world. Aristotle’s two main concepts of motion are that all elements move in a certain direction and towards a fixed point, and that all unnatural motion requires a force (Campbell and Campbell 2016) (Guthrie, n.d.). Aristotle uses these concepts of motion to demonstrate that the Earth is the centre of motion, or the fixed point around which the planets and elements move (Guthrie, n.d.). He argues that if the world isn’t the centre of the universe and the centre of motion and that if there existed another world like it, the order and variety we see wouldn’t exist (Campbell and Campbell 2016) (Guthrie, n.d.). Aristotle argued that the Earth is unique and that if there existed a place exactly like it, that place would hold the same properties as earth and therefore two centres would exist (Guthrie, n.d.). If two centres existed, Aristotle argued that the elements of the other world would move towards Earth and vice-versa, which is impossible (Campbell and Campbell 2016) (Guthrie, n.d.) (‘Aristotle’S Natural Philosophy (Stanford Encyclopedia Of Philosophy)’ 2006).

In Book 2 of On the Nature of Things, Lucretius describes his concept of the motion of atoms to explain the Epicurean worldview and shows how this concept explains the order and variety in the world (Simpson, n.d.) (Sedley 2005). The Epicurean world view proposes that there is are two fundamental entities that make up the world, matter/atoms and void (Simpson, n.d.) (Sedley 2005) (Shepards 2019). Essentially, atoms are the indivisible, minute building blocks of the natural world (Simpson 2020). It is through the combination of atoms that the physical world is built (Simpson, n.d.) (Sedley 2005). Furthermore, according to the Epicurean worldview, atoms have a natural downward motion at a uniform velocity (Simpson, n.d.). As a result, all change in the universe comes from changes to this natural motion and the resulting collision of atoms (Simpson, n.d.) (Shepards 2019). Therefore, Lucretius’ concept of the motion of atoms is essential to explaining his Epicurean worldview and the order and variety he sees in the world. Throughout the poem, Lucretius using the metaphor of dust mites in a sunlight room, describes the motion of atoms as continuous and endless, and describes how sometimes they meet and clash to account for his Epicurean worldview (On The Nature Of Things Book II 2019).

In conclusion, both philosophers use their differing concepts of atomic or planetary motion to underpin their views of the natural world. When analysing both Lucretius’ and Aristotle’s natural world views, it’s obvious that their views of the world greatly underpinned by fundamental concepts of motion. Aristotle broke down the natural world into four elements and believed the world was the centre of the universe because of the phenomenon he observed. Thanks to his observation that Earth is unique and is the fixed point for all planetary motion, Aristotle uses this theory of motion to account for happenings in the natural world. On the other hand, Lucretius believed that the world is made up of atoms and void, and that all change in the universe comes from changes to the natural downward motion of atoms. He uses this Epicurean world view to explain the variety he observes in the natural world. Though their ideas of the natural world differ greatly, both Aristotle and Lucretius underpinned their views with fundamental concepts of motion.

References

1. ‘Aristotle’S Natural Philosophy (Stanford Encyclopedia Of Philosophy)’. 2006. Plato.Stanford.Edu. https://plato.stanford.edu/entries/aristotle-natphil/#Moti.
2. Campbell, Dylan, and Dylan Campbell. 2016. ‘Aristotle’s On The Heavens’. Ancient History Encyclopedia. https://www.ancient.eu/article/959/aristotles-on-the-heavens/.
3. Guthrie, W.K.C. n.d. Aristotle On The Heavens. Boston: Harvard University Press.
4. On The Nature Of Things Book II. 50 BCE. Translated from the Latin by William Ellery Leonard.
5. Sedley, David. 2005. ‘Lucretius (Stanford Encyclopedia Of Philosophy)’. Plato.Stanford.Edu. https://plato.stanford.edu/entries/lucretius/#Phy.
6. Shepards, Sam. 2019. ‘The Epicurean Worldview’. Owlcation. https://owlcation.com/humanities/The-Epicurean-Worldview.
7. Simpson, David. n.d. ‘Lucretius | Internet Encyclopedia Of Philosophy’. Iep.Utm.Edu. https://www.iep.utm.edu/lucretiu/#SSH2b.i.