I saw someone say that an autistic girl in their class said that nobody should have lied to protect Anne Frank; and this was viewed with humour. Kant would have agreed with the autistic girl, and he would have agreed for the following reason: we cannot know what would have happened if nobody had lied to protect the Frank family; however, we do know that the final outcome from those lies that were told to protect the Frank family was that the family was deported and—mostly—killed. In other words, those lies were causative in Anne Frank’s deportation and death; we know this for certain—if lies had not been told, she might have been deported at a different time and survived; perhaps she would have not been deported at all. Ergo, it was wrong to lie to protect her—and not just because these particular lies led to a negative outcome but because to lie establishes a general principle that lies should be how we engage with the world.
The example Kant used—analogous to the Frank case—was a man who turns up at your house and seeks shelter from someone who wants to kill him. You tell him to go to your attic. Moments later, a man with an axe turns up and demands to know where the man you have hidden has gone. Kant said that if you lied and said, for example, that he just slipped past you into the kitchen and out the back gate that the axeman might catch him at the back gate because there is no guarantee that the man you hid had not done just that without your knowledge—perhaps he changed his mind when you ushered him towards the attic. If he has done that and you truthfully say, “He’s in the attic,” then, if he made a run for the back gate, you have saved his life.
This all sounds, I suspect, somewhat hypothetical; surely, on the balance of probabilities, the man will have trusted you and gone to your attic, so to tell the truth almost certainly condemns him to death—similarly, whenever Frank was deported she was probably going to die; so it seems likely that lies, at the very least, stave off the inevitable.
I think Kant would reply that we cannot really know that, but we do know that the particular lies told to protect Frank led to her death and so are demonstrably implicated in a negative event; perhaps if the Frank family had made commitment not to live by deception from the very first they would have fled Europe as soon as Hitler came to power, for they would have inferred that to survive in such a regime would require them to lie and—if they took the categorical imperative seriously—they would have left Germany for somewhere they did not have to lie constantly. In other words, a person’s complicity in lies—in willing a world where lies are a normal mode of defence—leads them to disaster.
Kant would say that we should act with regard to what the world would look like if everyone acted as we did, to act as if our particular action is a generalisable rule—this is the categorical imperative. From this perspective, the Franks were in a mess because they were enmeshed in a world where the categorical imperative was “lie to defend yourself.”
Hitler was in power because of the First World War and Weimar Germany, both lie-heavy events; he himself—though relatively honest, hence shocking—was also engaged in various lies; so the entire situation, in Kantian terms, was the logical outcome from a will to universalise values that ultimately harm everyone. The only solution is to consider the implications if you allow a generous “lie regime” and what the world would be like if everyone did it and then act accordingly. Then again, they say Kant, with his unchanging clockwork daily walk, was a little autistic.