The reversal test is a

heuristic A heuristic (; ), or heuristic technique, is any approach to problem solving or self-discovery that employs a practical method that is not guaranteed to be optimal, perfect, or rational, but is nevertheless sufficient for reaching an immediat ...

designed to spot and eliminate

status quo bias Status quo bias is an emotional bias; a preference for the maintenance of one's current or previous state of affairs, or a preference to not undertake any action to change this current or previous state. The current baseline (or status quo) is tak ...

, an emotional bias irrationally favouring the current state of affairs. The test is applicable to the evaluation of any decision involving a potential deviation from the status quo along some continuous dimension. The reversal test was introduced in the context of the

bioethics Bioethics is both a field of study and professional practice, interested in ethical issues related to health (primarily focused on the human, but also increasingly includes animal ethics), including those emerging from advances in biology, med ...

human enhancement Human enhancement (HE) can be described as the natural, artificial, or technological alteration of the human body in order to enhance physical or mental capabilities. Technologies Existing technologies Three forms of human enhancement curre ...

Nick Bostrom Nick Bostrom ( ; sv, Niklas Boström ; born 10 March 1973) is a Swedish-born philosopher at the University of Oxford known for his work on existential risk, the anthropic principle, human enhancement ethics, superintelligence risks, and th ...

and

Toby Ord Toby David Godfrey Ord (born July 1979) is an Australian philosopher. He founded Giving What We Can in 2009, an international society whose members pledge to donate at least 10% of their income to effective charities, and is a key figure in the ...

Reversal test

Bostrom and Ord introduced the reversal test to provide an answer to the question of how one can, given that humans might suffer from irrational status quo bias, distinguish between valid criticisms of proposed increase in some human trait and criticisms merely motivated by resistance to change. The reversal test attempts to do this by asking whether it would be a good thing if the trait was ''decreased'': An example given is that if someone objects that an increase in intelligence would be a bad thing due to more dangerous weapons being made etc., the objector to that position would then ask "Shouldn't we decrease intelligence then?"

"''Reversal Test'': When a proposal to change a certain parameter is thought to have bad overall consequences, consider a change to the same parameter in the opposite direction. If this is also thought to have bad overall consequences, then the onus is on those who reach these conclusions to explain why our position cannot be improved through changes to this parameter. If they are unable to do so, then we have reason to suspect that they suffer from status quo bias." (p. 664)

Ideally the test will help reveal whether status quo bias is an important causal factor in the initial judgement. A similar thought experiment in regards to dampening traumatic memories was described by Adam J. Kolber, imagining whether aliens naturally resistant to traumatic memories should adopt traumatic "memory enhancement". The "trip to reality" rebuttal to Nozick's

experience machine The experience machine or pleasure machine is a thought experiment put forward by philosopher Robert Nozick in his 1974 book '' Anarchy, State, and Utopia''. It is an attempt to refute ethical hedonism by imagining a choice between everyday real ...

thought experiment (where one's entire current life is shown to be a simulation and one is offered to return to reality) can also be seen as a form of reversal test.

Double reversal test

A further elaboration on the reversal test is suggested as the double reversal test:

"''Double Reversal Test'': Suppose it is thought that increasing a certain parameter and decreasing it would both have bad overall consequences. Consider a scenario in which a natural factor threatens to move the parameter in one direction and ask whether it would be good to counterbalance this change by an intervention to preserve the status quo. If so, consider a later time when the naturally occurring factor is about to vanish and ask whether it would be a good idea to intervene to reverse the first intervention. If not, then there is a strong
prima facie ''Prima facie'' (; ) is a Latin expression meaning ''at first sight'' or ''based on first impression''. The literal translation would be 'at first face' or 'at first appearance', from the feminine forms of ''primus'' ('first') and ''facies'' (' ...
case for thinking that it would be good to make the first intervention even in the absence of the natural countervailing factor." (p. 673)

As an example, consider the parameter to be

life expectancy Life expectancy is a statistical measure of the average time an organism is expected to live, based on the year of its birth, current age, and other demographic factors like sex. The most commonly used measure is life expectancy at birth ...

, moving in the downward direction because of a sudden natural disease. We might intervene to invest in better health infrastructure to preserve the current life expectancy. Now if the disease is cured, the double reversal test asks: should we reverse our investment and defund the health services we created since the disease, now that it's gone? If not, perhaps we should invest in health infrastructure even if there never is a disease in the first place. In this case the status quo bias is turned against itself, greatly reducing its impact on the reasoning. It also purports to handle arguments of evolutionary adaptation, transition costs, risk, and societal ethics that can counter the other test.

Criticism

Alfred Nordmann argues that the reversal test merely erects a

straw-man A straw man (sometimes written as strawman) is a form of argument and an informal fallacy of having the impression of refuting an argument, whereas the real subject of the argument was not addressed or refuted, but instead replaced with a false ...

argument in favour of enhancement. He claims that the tests are limited to approaches that are

consequentialist In ethical philosophy, consequentialism is a class of normative ethics, normative, Teleology, teleological ethical theories that holds that the wikt:consequence, consequences of one's Action (philosophy), conduct are the ultimate basis for judgm ...

and

deontological In moral philosophy, deontological ethics or deontology (from Greek: + ) is the normative ethical theory that the morality of an action should be based on whether that action itself is right or wrong under a series of rules and principles, r ...

. He adds that one cannot view humans as sets of parameters that can be optimized separately or without regard to their history. Christian Weidemann argues that the double reversal test can muddy the water; guaranteeing and weighing transition costs versus benefits might be the relevant practical ethical question for much human enhancement analysis.Weidemann, Christian. Towards a Heuristic for Nanoethics: The Onus of Proof in Applied Ethics. Uncovering Status Quo and Other Biases. In ''Size Matters: Ethical, Legal and Social Aspects of Nanbiotechnology and Nanomedicine'', Johann S. Ach, Christian Weidemann (eds.), LIT Verlag Münster 2009 (pp. 126–127)

References

{{Future of Humanity Institute Bioethics Applied ethics Transhumanism Heuristics Nick Bostrom Change Thought experiments