In the Beginning, there was ... Philosophy.

In this Episode, I introduce the life and work of a forgotten hero of science: Alexander von Humboldt (1769-1859). In his own time he was such a famous explorer and discoverer that many of his contemporaries were influenced by his thinking, most notably Charles Darwin. And even though he is no longer as well known as Darwin today , many places, species, mountains and rivers are still named after him. He took a global approach to Nature, treating Nature as an interrelated whole, in which everything is in flux. He became the first ecologist who truly understood the importance of the environment and its influence on life. He approached Nature as a living organism. Politically, he was inspired by the ideals of the French revolution, which made him an opponent of colonialism and slavery. Literature: * Andrea Wulf: The Invention of Nature (2015; a magnificent biography, on which this episode is based) * Friedel Weinert: The Scientist as Philosopher (2004: Ch. I.2 in which I explain the emergence of this notion of nature) Websites: * https://plato.stanford.edu/entries/alexander-humboldt [https://plato.stanford.edu/entries/alexander-humboldt] * https://en.wikipedia.org/wiki/Alexander_von_Humboldt [https://en.wikipedia.org/wiki/Alexander_von_Humboldt]

This episode looks at three pre-Darwinian accounts of the development of organic nature: the Great Chain of Being, Design arguments (Paley) and Jean-Baptiste Lamarck's 'transformatism'. All of these accounts assume, in one way or another, that the explanation of organic life requires the postulation of purpose and design in nature. This assumption is in striking contrast with mechanical explanations in astronomy and physics. The idea of 'evolution' was well accepted before Darwin. But Darwin's achievement consists in the articulation of a testable mechanism - natural selection - which explained evolution, without requiring design and purpose. The episode ends with a succinct description of Darwin's 'revolution'. Literature: * J. C. Greene, ‘The Kuhnian Paradigm and theDarwinian Revolution in Natural History’, in: G. Gutting (ed.): Paradigms and Revolutions (1980: 297-320) * F. Weinert, Copernicus, Darwin & Freud (Wiley 2009)

In this episode I introduce a brief history of scepticism, that is the doubt whether we can have any certain knowledge of the external world. I start with the Greek philosopher Sextus Empiricus who lived in the second century AD. His arguments were taken up and developed by the French Renaissance writer Michel Montaigne (1533-1592). Two French philosophers - Marin Mersenne (1588-1648) and his friend Pierre Gassendi (1592-1655) - rejected this rather defeatist version of scepticism and proposed a more moderate form: it accepts that we can have knowledge of appearances but know nothing about their underlying causes. Modern scepticism, as represented by the philosopher Karl Popper and the physicist Sean Carroll, defends the idea of conjectural knowledge. Science knows about appearances and the underlying causes but this knowledge is conjectural because it is always at the risk of refutation and revision. Literature: * Sextus Empiricus, Outlines of Pyrrhonism * R. H. Popkin, The History of Scepticism (3rd edition 2003) * N. A. Pinillos, Why We Doubt (OUP 2023) * F. Weinert, Karl Popper - Professional Philosopher and Public Intellectual (Springer 2022).

This episode introduces the life and influential ideas of William of Ockham (1287-1347). He was a controversial figure in his own time and is famous for his principle, known as Ockham's razor. It is a principle of economy, adopted by many philosophers and scientists, including Cambridge physicist Stephen Hawking. Its modern version recommends to use as few principles as possible to explain a maximum of facts. Ockham himself advised not to make unnecessary assumptions and not to postulate that abstract terms - such as beauty, cathood or humanity, - lead an extra-mental existence of their own in some sort of Platonic realm. Literature: This episode is based on my article: 'A razor sharp mind', in The Times Higher Education Supplement (14.03. 1986). There are informative articles on Ockham in the Stanford Encyclopedia of Philosophy [https://plato.stanford.edu/entries/ockham/] and the Internet Encyclopedia of Philosophy [https://iep.utm.edu/ockham/].

There is the rather common view that the Middle Ages were an age of darkness, ignorance and religious intolerance. But how true is this image? This episode introduces the Middle Ages (1000 AD-1543) as a period of intellectual vitality. It gave rise natural philosophy, which is the precursor of modern science. It accomplished two things. The first task was to make the Bible and Christian religion compatible with the authoritative teachings of Aristotle. This compromise was achieved by two remarkable scholars: Albert the Great (Albertus Magnus, 1200-1280) and Thomas Aquinas (1224-1274). The second task was to recognise Aristotle's errors and develop alternative explanations of the observable events in the natural world. Such alternative explanations were developed by John Buridan (1300-1361) and Nicola Oresme (1325-1382), amongst other scholastic philosophers. Both were followers of William of Ockham's philosophy of nominalism (1287-1347) and the maxim called Ockham's razor. Literature: A. C. Crombie: Augustine to Galileo (1959) J. Hannam: God's Philosophers (2009)