The moral high ground is naturally surrounded by hills, and with hills come slopes—plenty of them and treacherous too. In popular debate over a wide range of political and social issues, no specter is conjured up more often or more eagerly than the slippery slope. The image is apparently so suggestive that it is often introduced with little corroboration and accepted with little demur. And yet, while the move to the slippery slope is not necessarily illicit, it is almost invariably proposed in highly charged and emotive areas, and in many cases the appeal is specious or evasive.
The general form of the slippery-slope argument could hardly be simpler: if you permit practice A (either innocuous or mildly objectionable), then it will lead inevitably to practice Z (obnoxious and highly undesirable). Slippery slopes are detected in a bewildering array of situations. Here are some classic examples:
One common feature of such arguments is to state that there is a slippery slope from A to Z but to keep quiet about stages B to Y. The most notable absentee is generally the most important—some justification of the alleged inevitability of A leading to Z. Focus is shifted to the horrors of Z, often painted in the most lurid colors, and it is hoped that the lack of any discussion of the merits or otherwise of practice A may pass unnoticed. In effect, argument is replaced by rhetoric. The wisdom of (say) allowing parents to choose the sex of their children should be considered on its own merits, and if it is found objectionable, it should arguably be disallowed. If that practice is itself found to be innocuous, it may be relevant to consider the supposed inevitability of its leading to some other practice that is objectionable. But the case may well be hard to make, as in real life, where there is a genuine danger of a slippery slope appearing, it is generally possible to introduce rules and guidelines to prevent uncontrolled slides down it.
The dangers of creeping social or political change are sometimes illustrated by the legend of the boiling frog. If your aim is to boil a frog, you will toil in vain (so the story goes) if you drop it into boiling water, as it will promptly hop out; such disappointment can be avoided, however, if you place the frog in cold water and bring it slowly to the boil. In the same way, amphibian-minded libertarians might argue, gradual erosion of our civil liberties may lead to a cumulative loss (or “power grab”) that would have been vigorously opposed if attempted at a single stroke. The socio-political theory is more plausible than the frog theory; the falsity of the latter should be assumed, not tested.
Dominoes, wedges and lines The slippery slope is not the only hazard to which the popular moralizer alerts us. The first precarious step onto a slippery slope often precipitates a downward plunge toward a forest of other verbal perils, where there is a clatter of falling dominoes, snowballs grow to monstrous proportions, floodgates are flung wide open, and every iceberg has hidden depths.
Just as one falling domino can knock over its neighbor and so initiate a chain of successive topplings, in the domino effect it is suggested that the occurrence of a particular undesirable event will trigger a sequence of similar events nearby. Its most notorious appearance was in 1954, when it inspired the “domino theory” put forward by US president Dwight Eisenhower to justify US intervention in Vietnam. According to this theory, allowing one country to fall into communist hands would inevitably lead to others in Southeast Asia following suit. In the event, the first domino (Vietnam) did topple, but with the notable exception of Cambodia, the predicted spread of communism throughout the region did not follow; the supposed inevitability in this case proved to be nothing of the kind.
A small crack in stone or wood can be progressively widened by driving in a wedge; in the same way, appealing to the figurative thin end of the wedge suggests that a small change in (say) a rule or law may be the beginning of, or excuse for, wholesale reform. The suggestion that the right to trial by jury should be withdrawn in complex fraud cases is regarded by some as the thin end of the wedge, as they suspect that the right will gradually be withdrawn in other (perhaps all) areas. The wedge theorists’ suspicion remains mere supposition until supported by evidence that policy-makers tend to exhibit wedge-using behavior in such circumstances.
A colorful and all-too-rarely used variant of the slippery slope, supposedly based on an Arabic fable, gives a delightful glimpse of the peculiar perils of life under canvas (or goatskin). The dire consequences of “letting the camel’s nose into the tent”—especially as the nose is by no means the most offensive part of a camel—are charmingly captured by the 19th-century American poet Lydia Howard Sigourney:
Once in his shop a workman wrought With languid hand, and listless thought, When through the open window’s space Behold!—a Camel thrust his face. “My nose is cold,” he meekly cried, “Oh, let me warm it by thy side.” Since no denial word was said, In came the nose,—in came the head, As sure as sermon follows text The long, excursive neck came next, And then, as falls the threatening storm In leap’d the whole ungainly form.
Aghast the owner gazed around, And on the rude invader frown’d, Convinc’d as closer still he prest, There was no room for such a guest, Yet more astonish’d, heard him say, “If incommoded, go your way, For in this place I choose to stay.” Oh, youthful hearts, to gladness born, Treat not this Arab lore with scorn. To evil habit’s earliest wile Lend neither ear, nor glance, nor smile, Choke the dark fountain ere it flows, Nor even admit the Camel’s Nose.
The problem in knowing where to draw the line usually arises from seeking certain knowledge where such knowledge is not possible—from expecting a degree of precision inappropriate to the context. We might all agree, for instance, that it would be wrong to allow many millions of immigrants to settle in the country each year and yet that it is right to allow some to do so. Where do we draw the line? The fact that there is necessarily a degree of vagueness about a decision or about the context in which it is made does not mean that it cannot or should not be made.
Exactly the same kind of problem has long plagued the debate over abortion, where many agree that a newly conceived embryo and a baby at full term are different, yet struggle (because it is impossible) to pinpoint a precise moment at which the change takes place. This is because the development of the fetus is a gradual process, and any point at which we choose to draw a line will be arbitrary to some extent. But this does not mean that any point is as good (or bad) as another, that no line should be drawn, or that any line that is drawn lacks authority or force.
the condensed idea
If you give them an inch …
| Timeline | |
|---|---|
| c.300BC | The sorites paradox |
| AD1785 | Ends and means |
| 1954 | Slippery slopes |