Co-operation & Community








What does it mean to be human?


Kevin Loughran


(see Main article)



Postscript: the power of imagination and atoms


Humans can imagine possibilities. Humans can imagine objects and materials being brought into existence that had not existed before. Humans can imagine a possible state of existence, a state of matter, beyond what they can see or touch.


At the beginning of the 18th Century the English chemist John Dalton presented an atomic theory. Drawing on previous research he concluded, firstly, that all gases consisted of tiny particles; and then that all matter consisted of such tiny particles, which he referred to as atoms (meaning 'indivisible'). He became convinced that each element was made up of different kinds of atom; and that it was the weight of their atoms that distinguished one element from the other.1


Not everyone accepted his ideas. It took over fifty years for his ideas to become a standard part of thinking about the elements.2 It was not until the early part of the 20th Century that definite proof of the existence of atoms was found. By the latter part of the 20th Century Richard Feynman could assert that "everything is made of atoms".3


Richard Feynman asked how we know that there are atoms. He answered that we know firstly by developing a hypothesis that there are atoms and then by conducting experiments that produce results, one after the other, that confirm the existence of atoms.4


But a theory developed to explain data provided by experiment and research is likely to begin with a "what if ...?"; a speculation about how things / the world might be


The idea that matter was composed of tiny particles moving around in the void was put forward first in Ancient Greece in the 5th Century B.C. by Leucippus. Then it was developed by Democritus and taken up later by Epicurus in the 4th Century B.C. (Although the idea was rejected by Aristotle.5


The ancient Greek theory of the atom has been dismissed as pure speculation not supported by experimental research: it was seen as representing simple intuition.6 But it was revived in the 17th Century by Pierre Gassendi. Gassendi and others at that time could accept the idea of the void in which (he argued) atoms moved because by that time experimental evidence for the existence of the void had been identified.7


John Dalton recognised the similarity between his theory and that of Leucippus and Democritus, so he used Democritus' term 'atom' (meaning indivisible). Although later research highlighted a complex inner structure for the atom, it didn't change the reality of the atom as the fundamental unit of matter and the elements, as Leucippus and Democritus had proposed.8


Although Leucippus and Democritus did not have the tools to explore the idea as later experimental scientists did, they could think about the world which they encountered. They could speculate about why it was the way it was, and imagine different states of existence from those which they could first see and touch. The atomic theory of Leucippus and Democritus was perhaps the greatest feat of pure imagination in the history of human thought.




Kevin Loughran


January 2017





1 John Gribben. Science: a history. London: Penguin, 2003. p. 368


2 ibid, p. 369


3 Richard Feynman. Six Easy Pieces. Penguin, 1988. p. 20


4 ibid. p. 18


5 James Garvey & Jeremy Stangran. The Story of Philosophy. London: Quercus, 2012. pp. 130-134.


6 e.g. Peter Atkins. Physical Chemistry: a very short introduction. Oxford University Press, 2014. p. 1


7 John Gribben. Science: a history. London: Penguin, 2003. pp. 116-117


8 Isaac Asimov. Asimov's Biographical Encyclopaedia of Science and Technology. London: Pan Books, 1975. p. 232

















Co-operation & Community 2017