Dear Dr. Boli: This fancy-pants toothpaste from the organic drug store says it contains activated charcoal. How do they activate charcoal? —Sincerely, A Man Reconsidering the Notion of Putting Black Toothpaste on His Toothbrush.

Dear Sir: Modern charcoal is usually activated by entering an activation code supplied by the manufacturer, which allows the charcoal to be activated by central servers. This precaution is necessary to prevent the chaos that would ensue if everybody could make charcoal without purchasing it from a reputable manufacturer. In the old days, of course, the activation code had to be sent by telegram, on receipt of which the manufacturer would dispatch a courier to the customer’s address with the activation key. It was a dangerous business being a charcoal activation courier, as they were frequently waylaid by miscreants who would stop at nothing to obtain the keys. For this as for at least one other reason (viz., the Magazine you are reading now), we may be grateful that we live in the age of the Internet.