[Y]ou must translate every bit of your Theology into the vernacular. This is very troublesome and it means you can say very little in half an hour, but it is essential. It is also of the greatest service to your own thought. I have come to the conviction that if you cannot translate your thoughts into uneducated language, then your thoughts were confused. Power to translate is the test of having really understood one’s own meaning.
I just discovered that quotation in C. S. Lewis, “Christian Apologetics” (God in the Dock, ed. Walter Hooper [W. B. Eerdmans, 1970, 2001], 98). If I had a philosophical code, what Lewis says here (replacing “Theology” with “philosophy”) would be the first in my list of pledges or demands-I-make-on-myself .
- Jargon is elitist and exclusionary. If I refuse to speak in language you can understand, I show you a baffling amount of disrespect. If you are my student, furthermore, I violate my duty to actually teach you if I lecture in jargon.
- Jargon is also cowardly. In obscuring what I am saying, and thus what I mean, it allows me to hide from criticism (both my own and others’).
- Moreover, jargon is cheap. It allows me to play with words instead of actually reasoning. And because it allows me to seem like I’m reasoning — while not actually requiring me to think — it is bad for me (like Lewis says).
Thus, if I do not speak in the vernacular when I teach, I violate my duty — and thus I violate the principles of justice. If I do not write in the vernacular, I violate the principles of courage. And if I cannot translate my thoughts into the vernacular, I fail to be intellectually virtuous.