Your philosopher may be the most careful, cognizant driver in the world—when they are not thinking or talking about philosophy. Give them an argument to ruminate over or a sparring partner, and suddenly your Ms./Mr.-fancy-pants-I-had-a-perfect-score-on-my-driving-test-and-even-know-obscure-traffic-rules-and-the-history-of-all-traffic-rules philosopher becomes, quite frankly, an octogenarian who forgot her/his glasses.
One of my facebook friends coined this phenomenon DUIP (Driving Under the Influence of Philosophy). DUIP is extremely dangerous to you and/or your philosopher and/or other philosophers and passengers (children, cats, etc).
Your philosopher may be able to talk about anything other than philosophy and/or may even be able to talk to another philosopher while driving, but if they happen into a philosophical conversation while driving, you may want to have an escape plan in place. Because I’m on an acronym kick today (I do work for a state university, after all, which is just one big jumble of acronyms), I came up with an acronym for protecting yourself and others from DUIP related incidents: LADI
L: Learn to recognize the signs of intoxication
If you hearken back to this article on philosopher-intoxication, I mention a few signs to look for. Also just be aware that intoxication is most likely to occur after extended periods talking with philosophers and hearing other philosophers give papers. A different sort of intoxication occurs after spending all day reading philosophy. This kind of intoxication is harder to identify. My favorite method is to ask the simple, “What did you do today?” before driving.
A: Avoid talking about philosophy in the car.
Your philosopher may view a car ride as the perfect time to discuss philosophy with you. Only discuss philosophy-things if your philosopher first agrees to give up the wheel to you. If your philosopher is adamant that they should be the drivers, try to either distract your philosopher with talk of other things.
D: Don’t let them drive.
This is the easiest way to avoid messy DUIP situations. It is also very obvious. This doesn’t work in our case, though, because my philosopher is a much better driver than me (except when philosophy-intoxicated).
I: If there is no other way around it (you are just friends and it is their car), distract, distract, distract.
Sometimes there is just no other way around the situation. Your philosopher may be a parent or friend or you could be in a situation where it would be awkward and/or impossible for you to drive (be under the legal driving age, have casts on both feet, etc). In these situations, it is better to sacrifice a little squeltching of your philosopher for safety. Some non-philosophers find it effective to “redirect” through forceful directions (shouting), but I prefer a more gentle approach of distracting my philosopher with a long story he might find interesting or a discussion about current events.
Here are some examples of distractions that might work:
1. Discussing a news or current events story.
2. Asking your philosopher about their family, childhood, and/or all-time favorite pets.
3. Sports (if your philosopher likes sports)
4. Discuss an event that happened at work and how you might interpret it.
5. Talk about fiction (books).
6. Ask about news from their academic department and/or university
[Philosophers, don't be offended at the simplicity of these topics. You have opinions about many of them, I am sure.]
Only you can prevent a DUIP accident. Remember to LADI and, when all else fails, grip the seat and close your eyes.
 I meant no offense to the elderly. Please do keep wearing your glasses, though, for both your safety and ours. :-)
 Obviously, I could have also structured these letters to spell LAID instead of LADI, but this is a “family” blog. I could see too many of you having fun with LAID.
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