The Guild of Alchemists had rules. Strict ones. Rules like “No indoor explosions after midnight,” "attempting to pass a duck through a singularuty is not allowed." and “DO NOT mix anything with sulphur unless you’ve said a proper goodbye to your loved ones.”

But rules, as the Arch-chancellor of Unseen University once remarked, are mostly things that happen to other people. As with many pronouncements of this sort, the Arch-chancellor later regretted this observation.

Take Horace, junior apprentice alchemist. Horace had what might politely be called _ideas_. And while most ideas in alchemy tend to involve smoke, sparks, and something green-ish dripping ominously through the ceiling, Horace’s involved stamps. Horace became the reason for the Arch-chancellor suffering ‘pronouncement remorse.’

And yes, it was all to do with stamps.

“Think about it,” he said, as another apprentice tried to scrape melted wax off the floor. “A postage stamp already carries a signia of authority. It’s tiny, it’s official, it says: this thing _means something_. So what if I enhanced it?”

“Enhanced?” said the other apprentice, who was busy bandaging a thumb.

“Embedded emotion into the ink. Happiness, for example. Imagine sending a letter that guarantees the reader feels euphoria when they open it.”

The apprentice gave him a long look. It was the look of someone who has seen a friend decide to test a new theory on “non-combustable fireworks.”

But Horace, of course, pressed on.

The experiment itself was a simple matter, which in alchemical terms means it only set inadvertent pyroclastic infernos for two benches and three spoons. He had mixed powdered cinnabar with tincture of optimism (illegal, naturally, but cheap if you knew the right dealer), and pressed it into the paper.

The result looked almost ordinary. Just a stamp, a little crooked around the edges, bearing, quite pleasantly, a faint shimmer if you squinted.

Horace stuck it onto an envelope and handed it to the apprentice. “Go on. Open it.”

The apprentice hesitated. Then tore it open.

And suddenly he was grinning, eyes wide, laughing at nothing at all. He danced in place, clapping his hands, as though he’d just discovered a source of free beer that improved with every sip.

Horace felt a small thrill of triumph. This was alchemical innovation. This was…

The apprentice collapsed in a heap, still smiling faintly.

Horace leaned over him. “Perhaps… a smidgin too much optimism.”

Of course, nothing remained secret for long in Murkstone-Snatchly. Within days, the Thieves’ Guild had got wind of the euphoric stamp. And if there’s one thing that spreads faster than fire in a paper warehouse, it’s the slightest soupçon, the merest whiff of profit.

Which brought the matter to the Patrician’s attention.

“Stamps that make people happy,” he said, steepling his fingers. “Do you see the danger, Drumknott?”

Drumknott, who had once received a cheerful tax demand and never quite recovered, nodded gravely.

“Yes, my lord. A city run on euphoria would be… unpredictable. It might even elect an actual clown as mayor.”

“Yes… We can’t have that sort of thing. And besides,” said the Patrician, “the stigma of such tampering could discredit the Post Office entirely. No one would trust a letter again. That would simply not do.”

Which is why, some days later, Horace was invited for a very polite conversation in a very quiet room.

And why, the next week, the Guild of Alchemists had a brand new ‘directive’ written in large letters in the Guilds’ Scroll of Service. Which is, in fact, a book of rules. It said, in an antique-looking and very hard-to-read script:

Under no circumstances:

“whether magical, alchemical, postal, philatelic, or otherwise pertaining to the application of adhesive-backed symbols upon paper or papery-like surfaces, shall stamps, stamp-shaped objects, or items exhibiting the qualities of stamps (including but not limited to squares, oblongs, perforations, or the faint suggestion of monarchs’ heads) be manufactured, distributed, licked, stuck, un-stuck, or otherwise meddled with within the bounds of the University precincts, or elsewhere in any place whatsoever, save in the unlikely event of written dispensation from the Arch chancellor, which will, in every case, not be given.” Further:

“The fabrication, invocation, or casual contemplation of postal adhesives, herein referred to as ‘stamps,’ ‘signia,’ or any other synonym deemed applicable by a committee of wizards who really ought to be doing something else, is expressly forbidden, owing to recent events that proved, conclusively, that the human nervous system was not designed for sudden bouts of unexplained euphoria while opening the mail.”

And:

“In the interests of public safety, interdimensional stability, and the continued non-combustibility of the Post Office, it is hereby decreed that the creation, collection, conjuration, or emotional enhancement of any item resembling a stamp (or stamps) is prohibited. This prohibition includes the use of stamps as metaphors, teaching aids, or illustrations on exam questions. Offenders will be reprimanded, fined, and exiled to the Outer Rims in perpetuity (or longer, as the Guild deems fit).”