Atomism is a philosophical doctrine which explains the versatility of the universe and its hierarchical structure. According to Atomists, everything in this reality is made up from the tiniest indivisible parts called atoms. The term “atom” stems from the word atoma used to denote objects that are impossible to divide in Greek. They have identical structure but their properties can differ. These invisible parts move chaotically and by means of collision produce various combinations or clusters of atoms, hence creating numerous objects in reality. Their internal movement happens in the void, where atoms can move freely. 

Another principal concept of Atomism is that the material objects created due to the combinations of atoms do not exist at all. Belonging to the materialistic philosophy, this tradition opposes theoretical disciplines as Metaphysics. According to organismic doctrine, the being and the matter cannot be split up into separate parts and needs to be studied as a single unity. Atomists totally rejected this doctrine with the existence of atoms and their clusters. The concept of Atomism was born in the philosophic traditions of such ancient countries as India and Greece around the 6th century BC. Centuries after centuries it developed into a completely different science which gave birth to numerous scientific advancements.

Types of Atomism 

The history of this philosophical school consists of two periods. The philosophical one represented by Indian and Greek philosophical schools examined the theoretical phenomena. The scientific period began in the 17th century. It marked a starting point of modern science. Then a shift of attention took place from the theoretical to practical one that is used to explain concrete scientific phenomena. Among the types of Atomism, several concepts can be distinguished. In Ancient Greece, Social Atomism was created to denote a theory which claims that society has to be studied on the basis of its separate individuals that are essential units of sociological analysis. 

Logical Atomism was elaborated in the 20th century within the framework of analytical philosophy. The British philosopher Bertrand Russell on the basis of the works of his teacher Ludwig Wittgenstein made an attempt to distinguish the smallest units of thinking impossible to be separated further. These are the atoms of thought and reasoning. Another doctrine called Simples Theory belongs to the study of various parts and their respective wholes called mereology. The notion of “simple,” the same as an atom, has no proper parts and is used to oppose the “gunk,” a whole that can be decomposed into smaller elements. 


Atomism in Ancient India

This doctrine was represented in India by three separate philosophical schools. One of the most outstanding Indian philosophers, Kanada, founded the Hindu Nyaya-Vaisesika School in the 6th century BC. This philosophical tradition argued that every atom has four elemental types. And these types possess 24 different qualities plus general and specific properties. They can pair into two combinations – dyads (a two-atom unity) and triads (a cluster of three atoms). Another important Indian school was founded in 4th century BC. The concepts of Buddhist Atomism were similar to the Nyaya-Vaisesika School but had a few divergences. 

For these philosophers, every atom has a certain characteristic and function revealed in the process of combining. A bright representative of this movement, Ghamakirti claimed that atoms are made of pure of pure energy. In the 1st century BC philosophers from the Jain School, an unorthodox Indian tradition also supported the building nature of atoms except for human souls. They explored the unities of atoms which could produce six different objects – karma, earth, shadow, water, unfit matter, and sense objects. In their discussions, the Jani philosophers theorized about the way atoms could move, react, or combine.

Greek Atomism

The followers of this materialistic philosophical school were the Greek thinkers Leucippus and Democritus. Leucippus cofounded the doctrine with his disciple Democritus in the 5th century BC. He worked out that the building matter of everything are atoms in their diverse chaotic combinations taking place in the infinite void where they move without limits. Atoms create various objects that people can touch, feel, smell, taste, etc. But, in fact, they do not exist. Plato was at odds with Democritus as to the absence of meaning in the movement of atoms. The philosopher proposed his theory of four basic elements – air, water, fire, and earth. Yet, they were not the essentials of this reality but geometric solids with triangular faces. By means of reassembling these triangles, atoms with diverse substance can be created. 

It was Aristotle who rejected the theory of atoms in the 4th century – he stated that the four elements (air, water, fire, and earth) have a permanent nature and can’t be made of separate particles. He believed that the existence of such notion as void totally violates the general rules of physics. The change happened not due to the collision of atoms but as a reaction to changes in reality. He also created the notion of minima naturalia (natural minimum). It denotes the smallest parts into which an organic and not-organic object can be divided. Another philosopher, Epicurus, didn’t object to Atomism but considered their theories too vague to explain the existence of different natural phenomena (earthquake, flood, and others). His disciple, Lucretius wrote a book entitled On the Nature of Things to illustrate the theory of Epicurus about the development of the world.

Western Atomism

Due to Aristotle, philosophers of the Medieval period didn’t have much information about this tradition until the 16th century. Two prominent scientists, Nicolaus Copernicus and Galileo Galilei, revived the philosophy of Atomism. Galileo Galilei used the knowledge about atoms as a founding concept to experiment with falling bodies and created the theory of matter. In England, the followers of Atomism were known as the Northumberland Circle. Sir Francis Bacon and Thomas Hobbs belonged to this group. Those were French philosophers Rene Descartes, Pierre Gassendi, and an Irish scholar Robert Boyle who returned the atomic philosophy from its exile. 

Being a representative of the mechanical philosophy, Descartes viewed the universe as a big mechanism. The smallest parts of this world he called corpuscles. The way humans experience various sensations depends on the size or form of these parts. Until this point, his theory corresponds to the atomic concepts. Yet, in his philosophy, Descartes rejects the existence of void – no vacuum is possible for change to take place. This is the principal difference that distinguishes these two theories. He also developed the idea of the duality of human body and soul, which wasn’t favored by Pierre Gassendi.

A Catholic priest, Gassendi aimed at purifying the atomic tradition from any heretic concepts. He created his own type of mechanical philosophy. Another Atomist who is believed to be the Father of Chemistry was Robert Boyle. His contribution to the branch is that he proved atoms exist in accordance with their relationship between pressure and gas. His theorem is called Boyle’s Law. He claimed that the four elements of Greek scholars couldn’t be combined to form any matter or be extracted from the object. He came up with a new definition of an atom based on his observation that these parts could be made of even smaller parts.

Atomic theory

The Industrial Revolution and development of technology have influenced theories about the components of the matter. In the 18th century, the foundations for a scientific atomic theory were laid by scholars from different scientific fields. The first mathematical atomic theory was created by Roger Boscovich who used the postulates of Newtonian mechanics. This inspired John Dalton to invent the chemical element. The scholar who is often regarded to be the father of the modern atomic theory, Dalton summarized all the factual evidence of the previous studies and explored that any chemical element consists of atoms of one particular type that can be bound to create more complicated chemical compounds. 

At the end of the 20th century, new studies were conducted to demonstrate that any atom is composed of tinier units which are electrons, protons, and neutrons. And even these parts can be decomposed. They have been proven to consist of fundamental microscopic particles – quarks. Due to the groundbreaking developments in chemistry, physics, and many other scientific disciplines, Atomism no longer has a pure philosophical meaning. That’s why the amount of philosophers supporting these doctrines nowadays is pretty scarce.