Sep 9, 2016 11:31 PM
Why science should avoid metaphysics: The philosopher who revived anti-realism
http://m.nautil.us/issue/40/learning/-wh...etaphysics
EXCERPT: Philosophers of science are not known for agreeing with each other—contrariness is part of the job description. But for thousands of years, from Aristotle to Thomas Kuhn, those who study what science is have roughly categorized themselves into two basic camps: “realists” and “anti-realists.”
In philosophical terms, “anti-realists” or “empiricists” understand science as investigating the properties of observable objects via experiments. Empirical theories are constrained by the experimental results. “Realists,” on the other hand, speculate more freely about the possible shape of the unobservable world, often designing mathematical explanations that cannot (yet) be tested. Isaac Newton was a realist, as are string theorists.
Most scientists do not lose sleep worrying about philosophical divides. But maybe they should; Albert Einstein certainly did, as did Niels Bohr, and Erwin Schrödinger. In the 20th century, Kuhn’s cataloguing of the “paradigmatic” nature of scientific revolutions entered the scientific consciousness. As did Karl Popper’s requirement that only theories that can in principle be determined to be false are scientific. “God exists,” for example, is not falsifiable.
But outside the halls of the academy, the influential works of philosophers of science, such as Rudolf Carnap, Wilfrid Sellars, Paul Feyerabend, and Bas C. van Fraassen, to list but a few, are little known to many scientists and the public.
As the inventor of “constructive empiricism,” van Fraassen is widely acknowledged by his peers as one of the greatest living philosophers. (He calls himself “a philosopher’s philosopher.”) Van Fraassen does not write for the philosophically uninitiated, but his books are in no danger of going out of print.
“In 1980, van Fraassen’s The Scientific Image singlehandedly changed the terms of the debate between scientific realism and empiricism,” says Jos Uffink of the University of Minnesota. “He rescued empiricism from the dead end of logical positivism.”
In his 2008 book, Scientific Representation: Paradoxes of Perspective, van Fraassen argued that experimental data is nothing more nor less than a representation of an observable fragment of a fundamentally unobservable universe. He argued that while it is scientifically acceptable to believe that data represents a physical state of an “it,” that does not necessarily mean “it” exists.
As the ineluctably empiricist philosopher, Ludwig Wittgenstein, quipped, “Whereof one cannot speak, thereof one must be silent.” And yet many scientists speak of unobservables as if they are embedded in a map of reality that can be discovered.
Constructive empiricism does not allow an empiricist to project truth onto the unobservable world—which van Fraassen likened to an “insidiously enchanted forest” in Scientific Representation. In the history of science, the enchanted forest has successively been populated with rain gods, musical spheres, phlogiston, ether, multiple universes, big bangs, cosmic inflation, dark matter, dark energy, and singularities. A scientist who believes in the existence of these unobserved entities has wandered into a thicket of metaphysical speculation, and left the realm of science, says van Fraassen.
Science is walled off from metaphysics in van Fraassen’s brand of empiricism by the demand that experimental data must correlate with at least part of the structure of a theoretical model. His bedrock notion of “empirical adequacy” stops at that, forbidding itself to speculate about the (metaphysical) nature of unobserved phenomena.
Fortunately, constructive empiricism allows science to proceed without providing an ontological map of the whole shebang. By way of example, there is evidence for what goes on inside a proton, but that does not allow us to assume the existence of quarks. Tons of data from linear accelerators fit into an empirically adequate model of what quarks might be. But to claim that quarks exist is a metaphysical, not a scientific statement.
Nautilus caught up with van Fraassen in July at a conference on “Quantum Interaction” at San Francisco State University [interview]....
What can Avicenna teach us about the mind-body problem?
https://aeon.co/ideas/what-can-avicenna-...dy-problem
EXCERPT: Philosophers of the Islamic world enjoyed thought experiments. [...] But the most famous is the so-called ‘flying man’ thought experiment, devised by the most influential philosopher of the Islamic world, Avicenna. Imagine, he says, that a person is created by God in mid-air, in good condition but with his sight veiled and his limbs outstretched so that he is touching nothing, not even his own body. This person has no memories, having only just been created. Will his mind be a blank, devoid as it is of past or present sensory experience? No, says Avicenna. He will be aware of his own existence. Three questions immediately arise.
[...] Now for the third, and hardest, question: what does the flying man thought experiment prove? Avicenna draws a surprising conclusion: it shows that we are not identical with our bodies. Just consider. The flying man is aware of himself; he knows that he exists. But he is not aware of his body; he doesn’t know that his body exists, nor indeed that any body exists. And if I am aware of one thing but not another, how can those two things be identical? This sounds pretty persuasive, until you reflect that one can be conscious of a thing without being conscious of everything about it....
http://m.nautil.us/issue/40/learning/-wh...etaphysics
EXCERPT: Philosophers of science are not known for agreeing with each other—contrariness is part of the job description. But for thousands of years, from Aristotle to Thomas Kuhn, those who study what science is have roughly categorized themselves into two basic camps: “realists” and “anti-realists.”
In philosophical terms, “anti-realists” or “empiricists” understand science as investigating the properties of observable objects via experiments. Empirical theories are constrained by the experimental results. “Realists,” on the other hand, speculate more freely about the possible shape of the unobservable world, often designing mathematical explanations that cannot (yet) be tested. Isaac Newton was a realist, as are string theorists.
Most scientists do not lose sleep worrying about philosophical divides. But maybe they should; Albert Einstein certainly did, as did Niels Bohr, and Erwin Schrödinger. In the 20th century, Kuhn’s cataloguing of the “paradigmatic” nature of scientific revolutions entered the scientific consciousness. As did Karl Popper’s requirement that only theories that can in principle be determined to be false are scientific. “God exists,” for example, is not falsifiable.
But outside the halls of the academy, the influential works of philosophers of science, such as Rudolf Carnap, Wilfrid Sellars, Paul Feyerabend, and Bas C. van Fraassen, to list but a few, are little known to many scientists and the public.
As the inventor of “constructive empiricism,” van Fraassen is widely acknowledged by his peers as one of the greatest living philosophers. (He calls himself “a philosopher’s philosopher.”) Van Fraassen does not write for the philosophically uninitiated, but his books are in no danger of going out of print.
“In 1980, van Fraassen’s The Scientific Image singlehandedly changed the terms of the debate between scientific realism and empiricism,” says Jos Uffink of the University of Minnesota. “He rescued empiricism from the dead end of logical positivism.”
In his 2008 book, Scientific Representation: Paradoxes of Perspective, van Fraassen argued that experimental data is nothing more nor less than a representation of an observable fragment of a fundamentally unobservable universe. He argued that while it is scientifically acceptable to believe that data represents a physical state of an “it,” that does not necessarily mean “it” exists.
As the ineluctably empiricist philosopher, Ludwig Wittgenstein, quipped, “Whereof one cannot speak, thereof one must be silent.” And yet many scientists speak of unobservables as if they are embedded in a map of reality that can be discovered.
Constructive empiricism does not allow an empiricist to project truth onto the unobservable world—which van Fraassen likened to an “insidiously enchanted forest” in Scientific Representation. In the history of science, the enchanted forest has successively been populated with rain gods, musical spheres, phlogiston, ether, multiple universes, big bangs, cosmic inflation, dark matter, dark energy, and singularities. A scientist who believes in the existence of these unobserved entities has wandered into a thicket of metaphysical speculation, and left the realm of science, says van Fraassen.
Science is walled off from metaphysics in van Fraassen’s brand of empiricism by the demand that experimental data must correlate with at least part of the structure of a theoretical model. His bedrock notion of “empirical adequacy” stops at that, forbidding itself to speculate about the (metaphysical) nature of unobserved phenomena.
Fortunately, constructive empiricism allows science to proceed without providing an ontological map of the whole shebang. By way of example, there is evidence for what goes on inside a proton, but that does not allow us to assume the existence of quarks. Tons of data from linear accelerators fit into an empirically adequate model of what quarks might be. But to claim that quarks exist is a metaphysical, not a scientific statement.
Nautilus caught up with van Fraassen in July at a conference on “Quantum Interaction” at San Francisco State University [interview]....
What can Avicenna teach us about the mind-body problem?
https://aeon.co/ideas/what-can-avicenna-...dy-problem
EXCERPT: Philosophers of the Islamic world enjoyed thought experiments. [...] But the most famous is the so-called ‘flying man’ thought experiment, devised by the most influential philosopher of the Islamic world, Avicenna. Imagine, he says, that a person is created by God in mid-air, in good condition but with his sight veiled and his limbs outstretched so that he is touching nothing, not even his own body. This person has no memories, having only just been created. Will his mind be a blank, devoid as it is of past or present sensory experience? No, says Avicenna. He will be aware of his own existence. Three questions immediately arise.
[...] Now for the third, and hardest, question: what does the flying man thought experiment prove? Avicenna draws a surprising conclusion: it shows that we are not identical with our bodies. Just consider. The flying man is aware of himself; he knows that he exists. But he is not aware of his body; he doesn’t know that his body exists, nor indeed that any body exists. And if I am aware of one thing but not another, how can those two things be identical? This sounds pretty persuasive, until you reflect that one can be conscious of a thing without being conscious of everything about it....
