Fecundity Without Falsification: The Universal Methodological Escape Hatch
There is a reason serious philosophy of science has always insisted that fecundity be tethered to falsifiability. Once that tether is cut, fecundity ceases to be a criterion and becomes a permission slip. And permission slips, once issued, are not honored selectively.
Serious philosophy of science treats “fruitfulness” (also called fertility or fecundity) as, at best, a secondary virtue in theory appraisal. Ernan McMullin, whose 1976 essay “The Fertility of Theory and the Unit for Appraisal in Science” remains the most authoritative treatment of the subject, made this explicit: fecundity matters when two hypotheses make comparable risky commitments, because one might open more testable lines of inquiry than the other. But once fruitfulness is promoted to a substitute for loss conditions, it stops functioning as a methodological virtue and becomes a permission structure. “Keep it if it keeps generating activity,” regardless of whether it could ever be wrong. That basic distinction between explanatory productivity and empirical vulnerability is part of the modern demarcation conversation in philosophy of science, even when authors disagree about exactly how to draw the boundary.
Michael Levin’s defense of Platonic Space rests increasingly on this maneuver. When pressed to specify what would falsify his hypothesis, he does not name an observation, an experiment, or a measurable outcome. Indeed, years after beginning to promote his Platonism, he’s yet to produce a single example of a successful lab prediction “inspired by” this framework beforehand. Instead, he offers a personal stopping rule and a large pile of IOU notes.
“I move on when I feel that it’s not being fruitful for new discoveries.”
If this definition of fecundity is accepted, then we must accept its consequences. And those consequences are not hypothetical. They are already with us.
The Slippery Currency of “Fruitfulness”
Under Levin’s formulation, a framework is justified so long as it continues to generate activity, papers, excitement, or internal motivation. It need not exclude any possible world. It need not risk failure. It need only persist. Like a London houseguest who never quite gets around to leaving, it requires only that the host not grow actively bored.
This is not a new standard. It is an abandoned one.
Karl Popper rejected it explicitly:
“Confirmation is a comparatively weak criterion, easily satisfied even by pseudo-scientific theories.”
Imre Lakatos was clearer still:
“A research programme which explains everything explains nothing.”
Yet Levin asks us to accept precisely this. If the idea continues to “bear fruit,” it stays. If not, it quietly retires. No falsifier required. No loss condition specified. One might as well claim that astrology remains viable because astrologers continue to find it personally fulfilling.
Now consider what follows if we take this seriously.
Discovery Institute Logic, Sanitized
The Discovery Institute has long argued that Intelligent Design should be taken seriously because it is “fruitful.” It motivates research. It reframes biology. It generates publications. It inspires new questions. Each year, it produces conferences, journals, and earnest graduate students convinced they are on the frontier of scientific revolution.
That claim has been rejected by every major scientific body not because Intelligent Design fails to inspire its proponents, but because it is structurally unfalsifiable. The problem was never that it lacked fecundity in Levin’s sense. ID theorists remain remarkably productive within their own ecosystem, churning out books and papers with impressive regularity. The problem was that it could not lose.
Once fecundity is detached from falsifiability, the Discovery Institute’s argument becomes valid. Not correct. Valid. If personal fulfillment and continued research activity constitute sufficient justification, then Intelligent Design has met the bar. It inspires. It generates questions. It produces literature. By Levin’s standard, it qualifies.
And what follows? The church then finds the Discovery Institute fecund. Creationist curricula become fecund. Theological explanations of suffering become fecund. Each layer inherits legitimacy from the one before it, not because evidence compels belief, but because belief continues to reproduce itself. Christopher Hitchens would have recognized this pattern immediately: it is the intellectual equivalent of passing a counterfeit bill. The first transaction may go unnoticed, but soon the entire currency collapses.
This is not a slippery slope argument. It is a well-documented historical pattern. Once unfalsifiable claims are granted scientific standing through appeal to fruitfulness alone, the boundary between legitimate inquiry and sophisticated pseudoscience dissolves entirely.
The Universal Alibi Problem
Hannah Arendt warned that when standards collapse, they do not collapse locally:
“The result of a consistent and total substitution of lies for factual truth is not that the lie will now be accepted as truth, and truth be defamed as lie, but that the sense by which we take our bearings in the real world (and the category of truth versus falsehood is among the mental means to this end) is being destroyed.”
If fecundity means “continues to feel useful to its adherents,” then racist pseudoscience qualifies. Eugenics qualified. Phrenology qualified. Social Darwinism qualified. Each generated research programs, journals, careers, and self-confirming communities. Each was, in its heyday, remarkably productive.
They were fecund. They were also catastrophically wrong.
The reason they were ultimately rejected was not a lack of creativity. It was exposure to falsification, ethical catastrophe, and empirical collapse. Phrenologists continued finding skull measurements fascinating right up until the moment when someone bothered to check whether their predictions actually worked.
Levin’s definition removes that exposure. It asks us to evaluate theories the way one might evaluate hobbies: do they bring joy? Do they inspire continued engagement? These are questions for dating apps, not for distinguishing science from pseudoscience.
“Let’s See How It Goes” Is Not a Safeguard
Levin reassures us that he will abandon Platonic Space if it stops producing results:
“If that research agenda nets no new discoveries, then I’ll move on.”
This is not a safeguard. It is a delay tactic masquerading as methodology.
A framework that cannot specify what would count as failure can always reinterpret outcomes as partial success, misunderstood signals, or premature measurement. The space is not mapped yet. The interface science is incomplete. The accounting needs revision. The constants may be deeper than physics. These are not hypotheticals; they are the standard repertoire of unfalsifiable frameworks under pressure. Every failed prediction becomes evidence that we simply haven’t understood the framework deeply enough yet.
Thomas Kuhn warned explicitly against confusing productivity with progress:
“Normal science often suppresses fundamental novelties because they are necessarily subversive of its basic commitments.”
But Kuhn never suggested that novelty excuses immunity from falsification. On the contrary, revolutions occur when theories break under pressure, not when their advocates tire of them. Phlogiston didn’t retire gracefully; it was destroyed by oxygen. The luminiferous ether didn’t decide to move on; it was annihilated by the Michelson-Morley experiment.
Levin’s criterion would have granted both theories indefinite extension. After all, phlogiston theory remained remarkably productive right up until it collapsed. Researchers continued finding it useful, generating predictions, opening new avenues of inquiry. By the metric of “fruitfulness to adherents,” it should never have been abandoned.
Metaphysics With a Lab Coat
Levin insists he is not doing philosophy. This is rather like insisting one is not getting wet while swimming. The moment one replaces falsification with fecundity, one is doing metaphysics, whether one admits it or not. And not particularly good metaphysics at that.
W.V.O. Quine made the point starkly:
“To be is to be the value of a variable.”
Platonic Space introduces variables that do no measurable work while claiming causal relevance. When challenged, it retreats into metaphor. When praised, it returns as ontology. This oscillation is not methodological sophistication. It is evasion.
Nicholas Shackel named it for what it is:
“The motte-and-bailey doctrine allows one to move back and forth between positions, enjoying the advantages of both without paying the costs of either.”
Fecundity becomes the bridge that allows this movement without accountability. It is the permission slip that validates retreat to the motte while continuing to reap the rhetorical benefits of the bailey.
Why This Matters Now
Levin objects that he cannot control how others use his ideas. That is true, in precisely the way that it is true that one cannot control how a loaded gun behaves once handed to a stranger. But one can control whether one hands out loaded guns.
A criterion that legitimizes Intelligent Design today will legitimize something worse tomorrow. That is not moral panic. It is historical induction. The Discovery Institute did not invent bad epistemology; it inherited frameworks that others had rendered unfalsifiable and claimed the inheritance as its own.
Science does not protect itself by trusting intentions. Intentions, as Hitchens observed repeatedly, are among the cheapest commodities in human affairs. Science protects itself by enforcing loss conditions.
Daniel Dennett put it plainly:
“A theory that explains everything explains nothing, and a theory that explains nothing can never be wrong.”
Levin’s fecundity asks us to accept a theory that cannot be wrong so long as it remains interesting. This is not scientific methodology. It is a book club with laboratory equipment.
The Verdict Fecundity Delivers
If fecundity means what Levin says it means, then every resilient belief system qualifies. The Discovery Institute qualifies. Religious extremism qualifies. Ideological pseudoscience qualifies. Each is fecund within its own ecosystem. Each generates research, publications, and true believers convinced they are at the vanguard of revolutionary insight.
The scientific community rejected these not because they lacked imagination (they possessed it in abundance), but because imagination is cheap. What is expensive is being wrong in public. What is rare is the willingness to specify the conditions under which one would admit defeat.
Fecundity without falsifiability is not a virtue. It is an alibi. And once admitted as valid methodology, it does not discriminate. It never has. It never will.
The phrenologists were very fecund. The eugenicists were extraordinarily fecund. The Lysenkoists were devastatingly fecund. Each produced mountains of research, each inspired devoted followers, each found their framework endlessly generative of new questions and insights. Each was also profoundly, catastrophically wrong.
What distinguished them from legitimate science was not lack of productivity. It was lack of falsifiability.
Levin’s definition erases that distinction. One can only hope he notices before someone else applies it to something considerably less benign than planarian regeneration.
References
McMullin, E. (1976). The Fertility of Theory and the Unit for Appraisal in Science. In R. S. Cohen, P. K. Feyerabend, & M. Wartofsky (Eds.), Boston Studies in the Philosophy of Science, Vol. 39: Essays in Memory of Imre Lakatos (pp. 395-432). Dordrecht: D. Reidel. https://doi.org/10.1007/978-94-010-1451-9_25 Annotation: The seminal and most authoritative treatment of fertility/fecundity as a theoretical virtue in philosophy of science. McMullin distinguishes between fertility as a legitimate secondary criterion when theories make comparable empirical commitments, versus fertility as a substitute for empirical adequacy, which he explicitly rejects.
Arendt, H. (1967). Truth and Politics. In Between Past and Future: Eight Exercises in Political Thought. New York: Viking Press. Original essay in The New Yorker, February 25, 1967.
Dennett, D. C. (1995). Darwin’s Dangerous Idea: Evolution and the Meanings of Life. New York: Simon & Schuster. ISBN 978-0684824710.
Kuhn, T. S. (1962). The Structure of Scientific Revolutions. Chicago: University of Chicago Press. ISBN 978-0226458083.
Lakatos, I. (1970). Falsification and the Methodology of Scientific Research Programmes. In I. Lakatos & A. Musgrave (Eds.), Criticism and the Growth of Knowledge (pp. 91-196). Cambridge: Cambridge University Press. ISBN 978-0521078269.
Lakatos, I. (1978). The Methodology of Scientific Research Programmes (Philosophical Papers, Vol. 1). Edited by J. Worrall & G. Currie. Cambridge: Cambridge University Press. ISBN 978-0521280310.
McMullin, E. (1982). Values in Science. PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association, 1982(2), 3-28.
Popper, K. R. (1963). Conjectures and Refutations: The Growth of Scientific Knowledge. London: Routledge. ISBN 978-0415043182.
Quine, W. V. O. (1948). On What There Is. Review of Metaphysics, 2(5), 21-38. Reprinted in Quine, W. V. O. (1953). From a Logical Point of View (pp. 1-19). Cambridge, MA: Harvard University Press. ISBN 978-0674323513.
Shackel, N. (2005). The Vacuity of Postmodernist Methodology. Metaphilosophy, 36(3), 295-320. https://doi.org/10.1111/j.1467-9973.2005.00372.x
Nolan, D. (1999). Is Fertility Virtuous in its Own Right? British Journal for the Philosophy of Science, 50(2), 265-282. https://doi.org/10.1093/bjps/50.2.265
Schindler, S. (2017). Theoretical Fertility McMullin-Style. European Journal for Philosophy of Science, 7(1), 151-173. https://doi.org/10.1007/s13194-016-0152-5
Segall, R. (2008). Fertility and Scientific Realism. British Journal for the Philosophy of Science, 59(2), 237-246. https://doi.org/10.1093/bjps/axn008
