An ad hoc argument is one in which a person shifts their goals or ‘moves the goalposts’ in mid-argument in order to avoid having to admit that they’re wrong. It tends to accompany defensiveness and a dogmatic attachment to a position that can’t possibly be accepted as wrong without losing face.

It’s also sometimes known as the ‘No True Scotsman’, from an example in which a Scotsman who claims that no Scotsman eats his porridge with sugar, when challenged with a counter-example of one who does, rejoins that no true Scotsman eats his porridge with sugar. The claim about the Scotsman in this example has thus shifted to a claim about a much more flexible and manipulable ‘true’ Scotsman. The ‘truth’ of the Scotsman seems to amount to nothing more than the favour of being defined as such by the ad hoc arguer, but of course ‘true’ sounds terribly grand and may deceive the unwary, even though it turns out to be empty bluster when examined more closely.

More controversial contemporary versions of the ‘true Scotsman’, may include the ‘true Muslim’, the ‘true scientist’ or the ‘true Socialist’: the true Muslim may always be peaceful, the true scientist always provisional, and the true Socialist always committed to equality, thus allowing us to hang on to idealisations of these positions when challenged with counter-examples that show them to be rough labels for diverse traditions. It may still be the case that the overwhelming majority of Scots refuse to eat their porridge with sugar, and the overwhelming majority of Muslims are peaceful, but if we absolutely essentialise those categories it may be a way of repressing recognition of the minority who are not.

Another example of ad hoc argument is illustrated by the following cartoon, which is a version of a historical example from the life of Galileo. Here it is not the category of ‘Scotsman’ that is being defended, but an Aristotelian scientific theory that all celestial bodies from the moon upwards must be perfect spheres. In order to avoid questioning this theory, one of Galileo’s opponents came up with this highly implausible explanation of what he observed. Of course, it’s just possible that he might be right, but the defensive intention is pretty transparent (if you’ll forgive the pun).

Ad hoc argument departs from the Middle Way because it involves an absolutisation of the belief that is being defended. It is so absolutised that the alternatives being offered are just not seriously considered, and instead the person using the ad hoc argument just wants an excuse to dismiss the alternative. As with any absolutisation, it also has an opposite that is just as unhelpful, which in this case is the assumption that the theory being defended is unquestionably wrong. The problem with the transparent substance is not that we know it to be wrong, but that it is necessarily assumed to be right for defensive reasons, just as the problem with assuming all ‘true’ Muslims to be necessarily peaceful is not that there may not be a justifiable interpretation of Islam that would require peaceful behaviour, but that the assertion about ‘true’ Muslims is made to avoid acknowledgement of the violent ones who at least use the label ‘Muslim’.

Ad hoc argument is closely related to confirmation bias, the tendency to select from our experience and interpret it in terms of our existing beliefs. It can also be seen as a form of circular argument or ‘begging the question’. For example, in the Galileo example, Aristotle’s theory is supported by the belief that the moon is perfectly spherical despite appearances to the contrary, which in turn justifies the belief in Aristotle’s theory.

Ad hoc argument needs to be distinguished from some other reasons people may have for changing their position in the course of an argument. For example, it may be necessary to redefine one’s terms in the course of an argument in a way that is not defensive, but rather has the goal of reaching a helpful conclusion. For example, if you were having an argument about Christianity and started off with a very narrow definition of it (e.g. belief that Jesus is the son of God, meaning a supernatural entity), but then recognised that you could reach a more helpful agreement with another person by recognising that Christianity could be defined in different ways (e.g. as a symbolic or archetypal relationship with a Christ-figure within our experience), shifting your definition would not be ad hoc argument. In the end, it’s the unhelpful disruption to engagement and mutual understanding involved in a particular shift in position that makes it ad hoc, not the mere fact of shifting one’s position.

Exercise

Are these examples of ad hoc argument?

1. The ‘Leave’ Campaign in the UK EU referendum pointed out that there have been 72 occasions (since the 1990’s) when the UK disagreed with new EU laws but was overruled. They argued that this involved unacceptable infringement of UK sovereignty.  However, the ‘Remain’ campaign responded that these 72 occasions should be seen in the context of over 2000 occasions when the UK has agreed with new EU laws, so that seen as a proportion rather than as a raw number it was not very high.
2. In a debate before a football game between England and Germany, an England fan predicted that England would win the game. In the event, England scored one undisputed goal, but Germany scored two goals, both from penalties awarded in controversial refereeing decisions. After the game, the fan argued that he had been correct, because England should have won the game if the referee had been fair.
3. Two Christians are discussing the interpretation of the Bible in relation to the ordination of women, which one supports but the other opposes. In 1 Corinthians 14:33-35 it says: “As in all congregations of God’s people, women should keep silent at the meeting. They have no permission to talk, but should keep their place as the law directs. If there is something they want to know, they can ask their husbands at home. It is a shocking thing for a woman to talk at the meeting.” The first Christian argues that this passage clearly implies that women should not be ordained, as one could hardly be an ordained priest or minister and not speak at a church service. The second argues that Paul’s motive when he wrote this passage was to prevent conflict between early Christians and the surrounding Roman culture, and that there is no reason why it should be interpreted as a commandment for Christians today.

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