Citation for this page in APA citation style.           Close


Mortimer Adler
Rogers Albritton
Alexander of Aphrodisias
Samuel Alexander
William Alston
Louise Antony
Thomas Aquinas
David Armstrong
Harald Atmanspacher
Robert Audi
Alexander Bain
Mark Balaguer
Jeffrey Barrett
William Belsham
Henri Bergson
George Berkeley
Isaiah Berlin
Richard J. Bernstein
Bernard Berofsky
Robert Bishop
Max Black
Susanne Bobzien
Emil du Bois-Reymond
Hilary Bok
Laurence BonJour
George Boole
Émile Boutroux
Michael Burke
Lawrence Cahoone
Joseph Keim Campbell
Rudolf Carnap
Ernst Cassirer
David Chalmers
Roderick Chisholm
Randolph Clarke
Samuel Clarke
Anthony Collins
Antonella Corradini
Diodorus Cronus
Jonathan Dancy
Donald Davidson
Mario De Caro
Daniel Dennett
Jacques Derrida
René Descartes
Richard Double
Fred Dretske
John Dupré
John Earman
Laura Waddell Ekstrom
Herbert Feigl
Arthur Fine
John Martin Fischer
Frederic Fitch
Owen Flanagan
Luciano Floridi
Philippa Foot
Alfred Fouilleé
Harry Frankfurt
Richard L. Franklin
Michael Frede
Gottlob Frege
Peter Geach
Edmund Gettier
Carl Ginet
Alvin Goldman
Nicholas St. John Green
H.Paul Grice
Ian Hacking
Ishtiyaque Haji
Stuart Hampshire
Sam Harris
William Hasker
Georg W.F. Hegel
Martin Heidegger
Thomas Hobbes
David Hodgson
Shadsworth Hodgson
Baron d'Holbach
Ted Honderich
Pamela Huby
David Hume
Ferenc Huoranszki
William James
Lord Kames
Robert Kane
Immanuel Kant
Tomis Kapitan
Jaegwon Kim
William King
Hilary Kornblith
Christine Korsgaard
Saul Kripke
Andrea Lavazza
Christoph Lehner
Keith Lehrer
Gottfried Leibniz
Jules Lequyer
Michael Levin
George Henry Lewes
David Lewis
Peter Lipton
C. Lloyd Morgan
John Locke
Michael Lockwood
E. Jonathan Lowe
John R. Lucas
Alasdair MacIntyre
Ruth Barcan Marcus
James Martineau
Storrs McCall
Hugh McCann
Colin McGinn
Michael McKenna
Brian McLaughlin
John McTaggart
Paul E. Meehl
Uwe Meixner
Alfred Mele
Trenton Merricks
John Stuart Mill
Dickinson Miller
Thomas Nagel
Otto Neurath
Friedrich Nietzsche
John Norton
Robert Nozick
William of Ockham
Timothy O'Connor
David F. Pears
Charles Sanders Peirce
Derk Pereboom
Steven Pinker
Karl Popper
Huw Price
Hilary Putnam
Willard van Orman Quine
Frank Ramsey
Ayn Rand
Michael Rea
Thomas Reid
Charles Renouvier
Nicholas Rescher
Richard Rorty
Josiah Royce
Bertrand Russell
Paul Russell
Gilbert Ryle
Jean-Paul Sartre
Kenneth Sayre
Moritz Schlick
Arthur Schopenhauer
John Searle
Wilfrid Sellars
Alan Sidelle
Ted Sider
Henry Sidgwick
Walter Sinnott-Armstrong
Saul Smilansky
Michael Smith
Baruch Spinoza
L. Susan Stebbing
Isabelle Stengers
George F. Stout
Galen Strawson
Peter Strawson
Eleonore Stump
Francisco Suárez
Richard Taylor
Kevin Timpe
Mark Twain
Peter Unger
Peter van Inwagen
Manuel Vargas
John Venn
Kadri Vihvelin
G.H. von Wright
David Foster Wallace
R. Jay Wallace
Ted Warfield
Roy Weatherford
C.F. von Weizsäcker
William Whewell
Alfred North Whitehead
David Widerker
David Wiggins
Bernard Williams
Timothy Williamson
Ludwig Wittgenstein
Susan Wolf


Michael Arbib
Walter Baade
Bernard Baars
Leslie Ballentine
Gregory Bateson
John S. Bell
Mara Beller
Charles Bennett
Ludwig von Bertalanffy
Susan Blackmore
Margaret Boden
David Bohm
Niels Bohr
Ludwig Boltzmann
Emile Borel
Max Born
Satyendra Nath Bose
Walther Bothe
Hans Briegel
Leon Brillouin
Stephen Brush
Henry Thomas Buckle
S. H. Burbury
Donald Campbell
Anthony Cashmore
Eric Chaisson
Gregory Chaitin
Jean-Pierre Changeux
Arthur Holly Compton
John Conway
John Cramer
E. P. Culverwell
Olivier Darrigol
Charles Darwin
Richard Dawkins
Terrence Deacon
Lüder Deecke
Richard Dedekind
Louis de Broglie
Max Delbrück
Abraham de Moivre
Paul Dirac
Hans Driesch
John Eccles
Arthur Stanley Eddington
Gerald Edelman
Paul Ehrenfest
Albert Einstein
Hugh Everett, III
Franz Exner
Richard Feynman
R. A. Fisher
Joseph Fourier
Philipp Frank
Steven Frautschi
Edward Fredkin
Lila Gatlin
Michael Gazzaniga
GianCarlo Ghirardi
J. Willard Gibbs
Nicolas Gisin
Paul Glimcher
Thomas Gold
A. O. Gomes
Brian Goodwin
Joshua Greene
Jacques Hadamard
Mark Hadley
Patrick Haggard
Stuart Hameroff
Augustin Hamon
Sam Harris
Hyman Hartman
John-Dylan Haynes
Donald Hebb
Martin Heisenberg
Werner Heisenberg
John Herschel
Art Hobson
Jesper Hoffmeyer
E. T. Jaynes
William Stanley Jevons
Roman Jakobson
Pascual Jordan
Ruth E. Kastner
Stuart Kauffman
Martin J. Klein
William R. Klemm
Simon Kochen
Hans Kornhuber
Stephen Kosslyn
Ladislav Kovàč
Leopold Kronecker
Rolf Landauer
Alfred Landé
Pierre-Simon Laplace
David Layzer
Benjamin Libet
Seth Lloyd
Hendrik Lorentz
Josef Loschmidt
Ernst Mach
Donald MacKay
Henry Margenau
James Clerk Maxwell
Ernst Mayr
John McCarthy
Warren McCulloch
Ulrich Mohrhoff
Jacques Monod
Emmy Noether
Abraham Pais
Howard Pattee
Wolfgang Pauli
Massimo Pauri
Roger Penrose
Steven Pinker
Colin Pittendrigh
Max Planck
Susan Pockett
Henri Poincaré
Daniel Pollen
Ilya Prigogine
Hans Primas
Adolphe Quételet
Jürgen Renn/a>
Juan Roederer
Jerome Rothstein
David Ruelle
Tilman Sauer
Jürgen Schmidhuber
Erwin Schrödinger
Aaron Schurger
Claude Shannon
David Shiang
Herbert Simon
Dean Keith Simonton
B. F. Skinner
Lee Smolin
Ray Solomonoff
Roger Sperry
John Stachel
Henry Stapp
Tom Stonier
Antoine Suarez
Leo Szilard
Max Tegmark
William Thomson (Kelvin)
Giulio Tononi
Peter Tse
Vlatko Vedral
Heinz von Foerster
John von Neumann
John B. Watson
Daniel Wegner
Steven Weinberg
Paul A. Weiss
John Wheeler
Wilhelm Wien
Norbert Wiener
Eugene Wigner
E. O. Wilson
Stephen Wolfram
H. Dieter Zeh
Ernst Zermelo
Wojciech Zurek
Konrad Zuse
Fritz Zwicky


Free Will
Mental Causation
James Symposium
Emil du Bois-Reymond

Emil du Bois-Reymond was a pioneering physiologist and the father of electrophysiology. He discovered the "action potential" that travels along a neuron when it "fires." Shortly after his discovery, Hermann von Helmholtz measured the speed of the action potential, about 30 meters/sec.

Du Bois-Reymond's philosophical ideas greatly influenced Ernst Cassirer, who argued for the importance of an objective and physical determinism alongside a subjective and spiritual freedom - a dualistic philosophy, probably inspired by Immanuel Kant's phenomenal and noumenal realms.

Cassirer's arguments, in turn, were a great influence on the early quantum physicists, including even Max Born, who was reluctant to press his discovery of irreducible chance in the form of quantum events that could only be predicted statistically.

In his book Determinism and Indeterminism in Modern Physics, Cassirer says of du Bois-Reymond

In his famous speech "Über die Grenzen des Naturerkennens" (1872) Emil du Bois-Reymond lifted the Laplacean formula out of its long oblivion and placed it at the focal point of epistemological and scientific discussion...

It claimed to fix once and for all the permanent, unalterable form of all scientific knowledge. At the same time, however, it regarded this very form as an insuperable limit. For du Bois-Reymond elevated scientific knowledge far above all accidental, merely empirical bounds. Within its own sphere he endowed it with a kind of omniscience. But this exaltation is only the precursor of its fall. From the heights of the strictest, most exact knowledge it is dashed into the abyss of ignorance, an ignorance from which nothing can deliver it, for it is not temporary and relative but final and absolute. If it were possible for human understanding to raise itself to the ideal of the Laplacean spirit, the universe in every single detail past and future would be completely transparent. "For such a spirit the hairs on our head would be numbered and no sparrow would fall to the ground without his knowledge. He would be a prophet facing forward and backward for whom the universe would be a single fact, one great truth." And yet this one truth would present only a limited and partial aspect of the totality of being, of genuine "reality." For reality contains vast and important domains which must remain forever and in principle inaccessible to the kind of scientific knowledge thus described. No enhancement or intensification of this knowledge can bring us a step nearer to the inner mysteries of being. Our knowledge dissolves into nothingness as soon as we leave the world of material atoms and enter the world of the "spirit," of consciousness. Here our understanding ends; for even with perfect, "astronomically exact" knowledge of all the material systems of the universe, including the system of our brain, it would still be impossible for us to comprehend how material being can give rise to the enigmatic appearance of consciousness.

Cassirer limits understanding to make room for spiritual mysteries, and follows positivism in denying the possibility of "explanations"
Accordingly the demand for "explanation" not only cannot be fulfilled here - strictly speaking it cannot even be raised: ignorabimus is the only answer that science can give to the question of the essence and origin of consciousness.

In the last decades of the nineteenth century the problem as thus put by du Bois-Reymond exercised a strong influence both on metaphysics and on the theory of scientific principles. Of course the attempt was made to escape from the radical consequences he had drawn. There was no ready surrender to the apodictic dogmatic conclusion of du Bois-Reymond's speech. But there seemed to be no doubt that here an important and pertinent problem had been raised with which epistemology and science had to wrestle using every power at their disposal. Even the neo-Kantian movement, which began in the early seventies almost at the time of du Bois-Reymond's speech, did not at first alter the situation substantially.

Bois-Reymond's speech [was made in] the period of controversy over materialism, when philosophy was confronted with the crisis of deciding whether to accept the guidance of scientific thought, which seemed to lead inevitably to a strictly mechanistic view of nature, or to maintain and defend its own position over against the scientific view, granting to the "spiritual" a different and special status.

For Cassirer, the work of du Bois-Reymond is to defend the spiritual elements of philosophy against materialism
It was here that du Bois-Reymond's speech took place, interpretable as a resolution of doubt and a way out of the dilemma. For it appeared to do justice to both claims, to satisfy in a certain sense the demands of materialism as well as those of systems having a place for the spiritual. Materialism and mechanism could find satisfaction in du Bois-Reymond's definition of science, for in this domain their basic maxims were not only recognized but set up as the sole and exclusive standard. "For us there exists nothing but mechanical knowledge," du Bois-Reymond emphasized, "no matter how miserable a substitute it is for true knowledge, and accordingly only one true form of scientific thought, that of mathematical physics." On the other hand, however, this form was rejected in regard to intrinsically transcendental problems. The scientist has to give up once and for all the idea of investigating these problems, leaving the way open for others to attempt purely speculative solutions. Thus the radical advocates of materialism as well as its bitterest opponents could appeal with equal right to du Bois-Reymond's basic thesis: the former, because they found enunciated in it the identity of scientific with materialistic, mechanistic thought, the latter because in addition a reality was assumed which was in principle inaccessible to scientific thought and which remained as a dark and impenetrable residue.

Du Bois-Reymond was quite wrong about determinism, which was equated with necessity in the eighteenth-century debates about freedom versus necessity. He is right that those debates turned into questions of freedom versus determinism in the nineteenth century, but they both assumed there were causal chains that threatened human freedom. See chapter 18 on "Cassirer's Thesis" in Ian Hacking's The Taming of Chance for more.

Hans Driesch (in his History and Theory of Vitalism, p.170) says that duBois-Reymond gave the latest anti-materialist teleological theories the name "Neov italism."

For Teachers
For Scholars

Chapter 1.5 - The Philosophers Chapter 2.1 - The Problem of Knowledge
Home Part Two - Knowledge
Normal | Teacher | Scholar