Are moral norms rooted in instincts? The sibling incest taboo as a case study

1. Are Moral Norms Rooted in Instincts? The Sibling Incest Taboo as a Case Study According to Westermarck's widely accepted explanation of the incest taboo, cultural prohibitions on sibling sex are rooted in an evolved biological disposition to feel sexual aversion toward our childhood coresidents. Bernard Williams posed the "representation problem" for Westermarck's theory: the content of the hypothesized instinct (avoid sex with childhood coresidents) is different from the content of the incest taboo (avoid sex with siblings)—thus the former cannot be causally responsible for the latter. Arthur Wolf posed the related "moralization problem": the instinct concerns personal behavior whereas the prohibition concerns everyone. This paper reviews possible ways of defending Westermarck's theory from the representation and moralization problems, and concludes that the theory is untenable. A recent study purports to support Westermarck's account by showing that unrelated children raised in the same peer groups on kibbutzim feel sexual aversion toward each other and morally oppose third-party intra-peer-group sex, but this study has been misinterpreted. I argue that the representation and moralization problems are general problems that could potentially undermine many popular evolutionary explanations of social/moral norms. The cultural evolution of morality is not tightly constrained by our biological endowment in the way some philosophers and evolutionary psychologists believe. 2. Power in Cultural Evolution and the Spread of Prosocial Norms According to cultural evolutionary theory in the tradition of Boyd and Richerson, cultural evolution is driven by individuals' learning biases, natural selection, and random forces. Learning biases lead people to preferentially acquire cultural variants with certain contents or in certain contexts. Natural selection favors individuals or groups with fitness-promoting variants. Durham (1991) argued that Boyd and Richerson's approach is based on a "radical individualism" that fails to recognize that cultural variants are often "imposed" on people regardless of their individual decisions. Fracchia and Lewontin (2005) raised a similar challenge, suggesting that the success of a variant is often determined by the degree of power backing it. With power, a ruler can impose beliefs or practices on a whole population by diktat, rendering all of the forces represented in cultural evolutionary models irrelevant. It is argued here, based on work by Boehm (1999, 2012), that, from at least the time of the early Middle Paleolithic, human bands were controlled by powerful coalitions of the majority that deliberately guided the development of moral norms to promote the common good. Cultural evolutionary models of the evolution of morality have been based on false premises. However, Durham (1991) and Fracchia and Lewontin's (2005) challenge does not undermine cultural evolutionary modeling in nonmoral domains. 3. A Debunking Explanation for Moral Progress According to "debunking arguments," our moral beliefs are explained by evolutionary and cultural processes that do not track objective, mind-independent moral truth. Therefore (the debunkers say) we ought to be skeptics about moral realism. Huemer counters that "moral progress"—the cross-cultural convergence on liberalism—cannot be explained by debunking arguments. According to him, the best explanation for this phenomenon is that people have come to recognize the objective correctness of liberalism. Although Huemer may be the first philosopher to make this explicit empirical argument for moral realism, the idea that societies will eventually converge on the same moral beliefs is a notable theme in realist thinking. Antirealists, on the other hand, often point to seemingly intractable cross-cultural moral disagreement as evidence against realism (the "argument from disagreement"). This paper argues that the trend toward liberalism is susceptible to a debunking explanation, being driven by two related non-truth-tracking processes. First, large numbers of people gravitate to liberal values for reasons of self-interest. Second, as societies become more prosperous and advanced, they become more effective at suppressing violence, and they create conditions where people are more likely to empathize with others, which encourages liberalism. The latter process is not truth tracking (or so this paper argues) because empathy-based moral beliefs are themselves susceptible to an evolutionary debunking argument. Cross-cultural convergence on liberalism per se does not support either realism or antirealism. 4. Realist Social Selection: How Gene–Culture Coevolution Can (but Probably Did Not) Track Mind-Independent Moral Truth Standard evolutionary debunking arguments (EDAs) in metaethics target moral beliefs by attributing them to natural selection. According to the debunkers, natural selection does not track mind-independent moral truth, so the discovery that our moral beliefs (realistically construed) were caused by natural selection renders them unjustified. I argue that our innate moral faculty is likely not the product of natural selection, but rather social selection. Social selection is a kind of gene–culture coevolution driven by the enforcement of collectively agreed-upon rules. Unlike natural selection, social selection is teleological and could potentially track mind-independent moral truth by a process that I term realist social selection: early humans could have acquired moral knowledge via reason and enforced rules based on that knowledge, thereby creating selection pressures that drove the evolution of our innate moral faculty. Given anthropological evidence that early humans designed rules with the conscious aim of preserving individual autonomy and advancing their collective interests, realist social selection appears to be an attractive theory for moral realists. However, I propose a new EDA to show that realist social selection is unlikely to have occurred. 5. A Debunking How-Possibly Explanation for the Principle of Universal Benevolence According to Street's evolutionary debunking argument (EDA), evolutionary biology provides "powerful" explanations of our "basic evaluative judgements." The discovery that our moral beliefs (realistically construed) are "saturated with evolutionary influence" renders them unjustified, since natural selection does not track mind-independent moral truth. De Lazari-Radek and Singer agree that most of our commonsense moral beliefs are debunked in the way Street claims, but they argue that belief in Sidgwick's principle of universal benevolence cannot be explained by natural selection and is therefore immune from EDAs. I argue that Street oversold the power of her evolutionary explanations, thus leaving an opening for realists to claim that moral beliefs with less powerful evolutionary explanations can escape debunking. In fact, all naturalistic theories of morality—including those invoked by Street and de Lazari-Radek and Singer—are speculative "how-possibly" explanations. If how-possibly explanations are not debunking, then both Street's (global) and de Lazari-Radek and Singer's (selective) debunking arguments fail. If how-possibly explanations are debunking, then selective debunkers must show that there is no plausible way that naturalistic forces could have produced the beliefs they want to defend. I argue that naturalistic how-possibly explanations can debunk moral beliefs by appealing to ontological parsimony, and provide a debunking how-possibly explanation for belief in the principle of universal benevolence

Effect of response format on cognitive reflection: Validating a two- and four-option multiple choice question version of the Cognitive Reflection Test

The Cognitive Reflection Test, measuring intuition inhibition and cognitive reflection, has become extremely popular since it reliably predicts reasoning performance, decision-making and beliefs. Across studies, the response format of CRT items sometimes differs, assuming construct equivalence of the tests with open-ended vs. multiple choice items (the equivalence hypothesis). Evidence and theoretical reasons, however, suggest that the cognitive processes measured by these response formats and their associated performances might differ (the non-equivalence hypothesis). We tested the two hypotheses experimentally by assessing the performance in tests with different response formats and by comparing their predictive and construct validity. In a between-subjects experiment (n = 452), participants answered an open-ended, a two- or a four-option response format of stem-equivalent CRT items and completed tasks on belief bias, denominator neglect and paranormal beliefs (benchmark indicators of predictive validity) as well as actively open-minded thinking and numeracy (benchmark indicators of construct validity). We found no significant differences between the three response formats in the number of correct responses, the number of intuitive responses (with the exception of the two-option version being higher than the other tests) and in the correlational patterns with the indicators of predictive and construct validity. All three test versions were similarly reliable but the multiple-choice formats were completed more quickly. We speculate that the specific nature of the CRT items helps to build construct equivalence among the different response formats. We recommend using the validated multiple-choice version of the CRT presented here, particularly the four-option CRT, for practical and methodological reasons

Open Data from the Third Observing Run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

Open data from the third observing run of LIGO, Virgo, KAGRA and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in April of 2019 and lasting six months, O3b starting in November of 2019 and lasting five months, and O3GK starting in April of 2020 and lasting 2 weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main dataset, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages.Comment: 27 pages, 3 figure

Search for subsolar-mass black hole binaries in the second part of Advanced LIGO’s and Advanced Virgo’s third observing run

We describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 M⊙–1.0 M⊙ and mass ratio q ≥ 0.1 in Advanced LIGO and Advanced Virgo data collected between 1 November 2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2yr−1 ⁠. We estimate the sensitivity of our search over the entirety of Advanced LIGO’s and Advanced Virgo’s third observing run, and present the most stringent limits to date on the merger rate of binary black holes with at least one subsolar-mass component. We use the upper limits to constrain two fiducial scenarios that could produce subsolar-mass black holes: primordial black holes (PBH) and a model of dissipative dark matter. The PBH model uses recent prescriptions for the merger rate of PBH binaries that include a rate suppression factor to effectively account for PBH early binary disruptions. If the PBHs are monochromatically distributed, we can exclude a dark matter fraction in PBHs fPBH ≳ 0.6 (at 90% confidence) in the probed subsolar-mass range. However, if we allow for broad PBH mass distributions we are unable to rule out fPBH = 1. For the dissipative model, where the dark matter has chemistry that allows a small fraction to cool and collapse into black holes, we find an upper bound fDBH < 10−5 on the fraction of atomic dark matter collapsed into black holes

Model-based cross-correlation search for gravitational waves from the low-mass X-ray binary Scorpius X-1 in LIGO O3 data

We present the results of a model-based search for continuous gravitational waves from the low-mass X-ray binary Scorpius X-1 using LIGO detector data from the third observing run of Advanced LIGO, Advanced Virgo and KAGRA. This is a semicoherent search which uses details of the signal model to coherently combine data separated by less than a specified coherence time, which can be adjusted to balance sensitivity with computing cost. The search covered a range of gravitational-wave frequencies from 25Hz to 1600Hz, as well as ranges in orbital speed, frequency and phase determined from observational constraints. No significant detection candidates were found, and upper limits were set as a function of frequency. The most stringent limits, between 100Hz and 200Hz, correspond to an amplitude h0 of about 1e-25 when marginalized isotropically over the unknown inclination angle of the neutron star's rotation axis, or less than 4e-26 assuming the optimal orientation. The sensitivity of this search is now probing amplitudes predicted by models of torque balance equilibrium. For the usual conservative model assuming accretion at the surface of the neutron star, our isotropically-marginalized upper limits are close to the predicted amplitude from about 70Hz to 100Hz; the limits assuming the neutron star spin is aligned with the most likely orbital angular momentum are below the conservative torque balance predictions from 40Hz to 200Hz. Assuming a broader range of accretion models, our direct limits on gravitational-wave amplitude delve into the relevant parameter space over a wide range of frequencies, to 500Hz or more

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$ $M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90\% confidence level.Comment: 24 pages, 5 figure

Search for subsolar-mass black hole binaries in the second part of Advanced LIGO's and Advanced Virgo's third observing run

We describe a search for gravitational waves from compact binaries with atleast one component with mass 0.2 $M_\odot$ -- $1.0 M_\odot$ and mass ratio $q\geq 0.1$ in Advanced LIGO and Advanced Virgo data collected between 1 November2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. Themost significant candidate has a false alarm rate of 0.2 $\mathrm{yr}^{-1}$. Weestimate the sensitivity of our search over the entirety of Advanced LIGO's andAdvanced Virgo's third observing run, and present the most stringent limits todate on the merger rate of binary black holes with at least one subsolar-masscomponent. We use the upper limits to constrain two fiducial scenarios thatcould produce subsolar-mass black holes: primordial black holes (PBH) and amodel of dissipative dark matter. The PBH model uses recent prescriptions forthe merger rate of PBH binaries that include a rate suppression factor toeffectively account for PBH early binary disruptions. If the PBHs aremonochromatically distributed, we can exclude a dark matter fraction in PBHs$f_\mathrm{PBH} \gtrsim 0.6$ (at 90% confidence) in the probed subsolar-massrange. However, if we allow for broad PBH mass distributions we are unable torule out $f_\mathrm{PBH} = 1$. For the dissipative model, where the dark matterhas chemistry that allows a small fraction to cool and collapse into blackholes, we find an upper bound $f_{\mathrm{DBH}} atomic dark matter collapsed into black holes.<br