Must science be testable?

Massimo Pigliucci
Aeon
Originally published August 10, 2016

Here is an excerpt:

hat said, the publicly visible portion of the physics community nowadays seems split between people who are openly dismissive of philosophy and those who think they got the pertinent philosophy right but their ideological opponents haven’t. At stake isn’t just the usually tiny academic pie, but public appreciation of and respect for both the humanities and the sciences, not to mention millions of dollars in research grants (for the physicists, not the philosophers). Time, therefore, to take a more serious look at the meaning of Popper’s philosophy and why it is still very much relevant to science, when properly understood.

As we have seen, Popper’s message is deceptively simple, and – when repackaged in a tweet – has in fact deceived many a smart commentator in underestimating the sophistication of the underlying philosophy. If one were to turn that philosophy into a bumper sticker slogan it would read something like: ‘If it ain’t falsifiable, it ain’t science, stop wasting your time and money.’

But good philosophy doesn’t lend itself to bumper sticker summaries, so one cannot stop there and pretend that there is nothing more to say. Popper himself changed his mind throughout his career about a number of issues related to falsification and demarcation, as any thoughtful thinker would do when exposed to criticisms and counterexamples from his colleagues. For instance, he initially rejected any role for verification in establishing scientific theories, thinking that it was far too easy to ‘verify’ a notion if one were actively looking for confirmatory evidence. Sure enough, modern psychologists have a name for this tendency, common to laypeople as well as scientists: confirmation bias.

Nonetheless, later on Popper conceded that verification – especially of very daring and novel predictions – is part of a sound scientific approach. After all, the reason Einstein became a scientific celebrity overnight after the 1919 total eclipse is precisely because astronomers had verified the predictions of his theory all over the planet and found them in satisfactory agreement with the empirical data.

The article is here.

A Fight for the Soul of Science

By Natalie Wolchover
Quanta Magazine
Originally published December 16, 2015

Here are two excerpts:

Critics accuse string theory and the multiverse hypothesis, as well as cosmic inflation — the leading theory of how the universe began — of falling on the wrong side of Popper’s line of demarcation. To borrow the title of the Columbia University physicist Peter Woit’s 2006 book on string theory, these ideas are “not even wrong,” say critics. In their editorial, Ellis and Silk invoked the spirit of Popper: “A theory must be falsifiable to be scientific.”

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Nowadays, as several philosophers at the workshop said, Popperian falsificationism has been supplanted by Bayesian confirmation theory, or Bayesianism, a modern framework based on the 18th-century probability theory of the English statistician and minister Thomas Bayes. Bayesianism allows for the fact that modern scientific theories typically make claims far beyond what can be directly observed — no one has ever seen an atom — and so today’s theories often resist a falsified-unfalsified dichotomy. Instead, trust in a theory often falls somewhere along a continuum, sliding up or down between 0 and 100 percent as new information becomes available. “The Bayesian framework is much more flexible” than Popper’s theory, said Stephan Hartmann, a Bayesian philosopher at LMU. “It also connects nicely to the psychology of reasoning.”

The entire article is here.

Replication, falsification, and the crisis of confidence in social psychology

By Brian D. Earp & David Trafimow
Front. Psychol. | doi: 10.3389/fpsyg.2015.00621

Abstract

The (latest) “crisis in confidence” in social psychology has generated much heated discussion about the importance of replication, including how such replication should be carried out as well as interpreted by scholars in the field. What does it mean if a replication attempt “fails”—does it mean that the original results, or the theory that predicted them, have been falsified? And how should “failed” replications affect our belief in the validity of the original research? In this paper, we consider the “replication” debate from a historical and philosophical perspective, and provide a conceptual analysis of both replication and falsification as they pertain to this important discussion. Along the way, we introduce a Bayesian framework for assessing “failed” replications in terms of how they should affect our confidence in purported findings.

The entire article is here.