The “slippery slope” argument is a well-known defence used by conservatives to oppose change. It has several metaphorical forms – such as the camel’s nose and the frog boiling. As an argument in logic it has no particular force. It’s not a matter of logic so much as a defence against unwanted changes. Even then, it has fairly fundamental weaknesses.
The most famous critique describes it as “deciding against doing good now, for fear of leading to bad things later”. So the slippery slope argument becomes a justification for wrongdoing: out of fear of consequences we choose to continue with doing wrong, or at least choose not to make a change to do what is right.
Furthermore, the slippery slope argument assumes inevitability. It assumes that if the camel gets its nose in the tent more of it inevitably will follow. But human actions are rarely inevitable and it’s sometimes possible to prevent foreseeable bad consequences.
Usually the argument jumps to the alarming end of the slope – the unacceptable, even unthinkable, consequence of change. This can be a fear tactic but can also be a form of the reductio ad absurdum argument – where there is agreement about the total undesirability of an outcome and the connection of the present proposal with producing that outcome. But to be sustained it has to be agreed that the end point is undesirable, that the present proposal will lead to the undesirable outcome and that there is no holding position between the present change and the final outcome.
With all these difficulties it may be surprising that people so often appeal to the slippery slope or one of its many versions (frogs, camels, dominoes, precedent, etc.). But the experience of life, the intuition about human nature and the knowledge of history persuade people of the incremental way in which society is changed. The high-minded arguments against censorship in the 1960’s have opened the floodgate of pornography of which the pro-censorship groups warned. Home computers have taken pornography well beyond the most dire warnings of the sixties.
Furthermore as society moves away from essentialist morality about right and wrong to a utilitarian outcome-based morality such as harm minimisation, so the argument of expected or predicted outcomes becomes more important. Why change the laws on drug use or gambling if there is not an expectation of better outcomes?
So, in a culture of ‘live and let live’, when should we pay attention to the slippery slope warnings and when should we dismiss them as alarmist and irrelevant to the morality of the present case?
One of the chief warnings to pay attention to is the use of the word “movement”. For the very nature of a movement is the desire to bring about an ongoing change. Its end point is not always clear, but its goal is reached through multiple actions heading in a particular direction.
So the “Charismatic Movement” of the 1960’s aimed at transforming the mainstream churches by re-introducing the Pentecostal experience. Such a movement couldn’t half-transform a church – thus the many half-way houses that conciliatory Christians suggested, all failed. Either a church embraces the movement or rejects it, accepting some of it inevitably leads to accepting more, because it is not a single issue but a reforming movement.
Similarly the Movement for the Ordination of Women (MOW) presented more than a single decision. It was an attempt to change the nature of the relationship between men and women in every aspect of church life. Intentionally each concession leads to the next demand for a change till ultimately all gender distinctions are removed. Ordination as presbyters was only a step towards consecration as bishops and that is only another step to the exclusion of all opponents to the movement. Proposed legislative half-way houses never worked, for wherever MOW has succeeded, its opponents have been subsequently excluded.
Another way of recognising the top of a slippery slope lies in the nature of the argument for taking the first step. If the first step requires a change in the nature of moral discourse, other consequences are likely to follow. This was true in both the Charismatic and women’s ordination issues. They both involved a call to significantly change Christian argument. In the Charismatic case it was a move away from the Bible interpreting our experiences to our experiences interpreting the Bible. Once that is allowed there is no end to the changes in theology that are possible. In the women’s ordination issue it was also a case of re-interpreting the Bible – this time in terms of culturally determined hermeneutics that either changed the meaning of New Testament teaching or made it no longer relevant to modern times. Either way the logic was such that other theological conclusions, notably the acceptance of sinful behaviour such as homosexuality, could not be resisted. Just as the acceptance of women’s ordination has lead to the exclusion of all opponents so it has lead to the acceptance of homosexuality and the persecution of its opponents.
Another marker of a slippery slide is the nature of the immediate change. A change in opinion will not have the same effect as a change in practice or personnel. To accept as genuinely spiritual, a practice that only some Christians have experienced, cannot but divide the church – establishing two kinds of Christians. To ordain women as presbyters or consecrate some as bishops cannot but divide diocese and denomination, creating ‘no-go-zones’ for those whose conscience binds them in opposition to such a development.
These issues are easy to see now, for the slide is demonstrable. The Charismatic movement has split the evangelical world. The ordination of women has ushered in wholesale persecution not only of its opponents but also those who oppose homosexual behaviour. The predictions were ignored – the reality has arrived. What is important is to rightly anticipate the effect of other proposed changes without being either conservatively alarmist or naively indulgent.