I was tempted to call this post something like “Don’t accept a slippery slope argument unless it is from a geocentrist in an arranged marriage” but that seemed a bit too long for a title.
As for myself, I think that slippery slope arguments should be dismissed outright when they are offered by anyone who is already on the slippery slope and yet claims not to be slipping.
Opponents of same-sex marriage use the argument. But few of them are in arranged patriarchal marriages of the sort the Bible takes for granted as what marriage is.
Self-proclaimed Biblical literalists use the argument. But few would say they literally think with their heart. And none I have met have given up all their property, yet they still say they are followers of Jesus.
And so those who talk about a slippery slope need to acknowledge, if they are honest, that it is possible to stop at arbitrary points on the slope – in which case it isn’t as slippery as they claim.
Or otherwise they should just lie back and enjoy the ride, because they are already on the slippery slope, and are presumably headed in your direction further down the hill!