When and How to Talk of One's Self : Page 211

Paradoxically, one may advance one's philosophy to complete and casual strangers more properly than to partial acquaintances. The smoking car of trains is the proverbial academy where personal philosophies are thrown about enthusiastically among complete and casual strangers. Whereas you should not tell a chance traveling companion what is in your heart, you may well tell him what is in your head. The Apostles approached strangers quite directly with their Gospel. Someone you meet casually need not come to like you. But he and you may learn from each other if you get into a political or religious discussion. Naturally, what was previously said about tact and courtesy you will obviously also scrupulously observe with strangers.