Li Shimin wishes to become a shareholder.

Although the grain Li Zhi purchased cost a little more than the original price, the difference was merely two or three coins for transportation. Such a trivial sum was nothing in Li Zhi's eyes. More than that, his actions directly inspired Li Shimin. Previously, for convenience, the court had handed over the grain acquisition tasks to the influential local clans. While this saved manpower, it also indirectly fostered a class of middlemen. The common people had barely seen any benefit, while the bulk of the profits went straight into the hands of these intermediaries.

Li Zhi’s method completely eliminated the exploitation by middlemen, ensuring the people directly reaped the benefits. Li Shimin saw even further possibilities. If the local authorities procured grain directly from the populace, they could gain a more accurate understanding of output, which would make it easier for the state to regulate grain prices. With government granaries established throughout the land, the court could control the supply of grain—preventing prices from soaring due to shortages, or from plummeting and harming farmers when there was a surplus.

When Li Shimin brought his ideas before the ministers, everyone once again marveled at Li Zhi’s ingenuity. Problems that had stymied them for ages seemed to dissolve effortlessly in his hands. Li Shimin and the court officials were delighted, but the clans who had been waiting to make a fortune now hated Li Zhi all the more. This time, however, no one was so reckless as to consider assassination. Instead, they devised a plan much like Li Tai’s: to humiliate Li Zhi in the realm of literature and thus find grounds to drive him out of the court. They were convinced that at such a young age, Li Zhi could not possibly have literary talent; otherwise, he would be more than a prodigy—he would be a god.

Thus, rumors began to circulate among the scholars, questioning whether Li Zhi’s focus on unorthodox pursuits was merely a cover for his lack of literary accomplishment. The architects of this gossip intended to force him into a grand literary gathering in the near future.

Li Zhi paid no heed to these conspiracies. He was busy promoting the honeycomb stove and honeycomb coal.

With the onset of winter, families within the resettlement area began installing honeycomb stoves. Following Li Zhi’s instructions, they assembled the stoves and started experimenting with their use. Li Zhi visited one household himself, guiding the man of the house to light a piece of honeycomb coal and place it in the stove. A single piece of coal did not produce much heat; it took nearly an hour just to boil a kettle of water. By then, the first piece was burning in earnest, and Li Zhi had the man add a second piece. The stove’s heat output quickly increased, and Li Zhi directed him to boil a second kettle. This time, it took less than half an hour for the water to boil, and the second piece of coal was only half consumed. With heat radiating from the stove and the chimney, the room grew noticeably warmer, forcing people to move away in search of cooler air.

After another half hour, Li Zhi asked for the final piece of coal to be added. At this point, only a tiny ember of the first remained. Li Zhi calculated in his mind and then asked Li Zhe, “If a piece of coal burns for an hour and a half, isn’t that comparable to charcoal?”

Li Zhe replied, “Your Highness jests. Though their burning time is similar, coal costs only a fifth as much as charcoal, and its applications far surpass charcoal’s.”

Li Zhe’s assessment was apt. High-quality charcoal was twenty coins per pound, and even mid-grade charcoal cost ten. Yet honeycomb coal, with a heat value similar to premium charcoal, sold for only five coins per piece. Moreover, honeycomb coal could be used directly for cooking and boiling water without wasting heat, something charcoal could not do. The only remaining obstacle was the dissemination of stoves. The output of pig iron in the Tang Empire had only recently increased, so the price for commoners was still high—about ten coins per pound. A honeycomb stove required about ten pounds of iron, and including other costs, each stove sold for two hundred coins.

Chimneys were also expensive. To ensure lightness, they were made from wrought iron, which, even after technological improvements, still cost twice as much as pig iron. Each chimney section weighed two pounds, and every household needed at least three or four. Including elbow joints and connectors, a set of chimneys started at ten pounds.

Thus, a chimney set alone cost nearly three hundred coins. With the stove, a complete setup amounted to five hundred coins—far beyond the means of ordinary families. After brief consideration, Li Zhi devised an installment plan: payments spread over five years, with only one hundred coins required per year to enjoy the benefits of the honeycomb stove. He also offered a honeycomb coal promotion: buy one hundred pieces and receive ten extra for free. With this, most commoners could afford the stoves, and sales would no longer be a problem.

These were products for the masses, and Li Zhi’s approach was high volume and low margin. With his sales strategy in place, he immediately instructed Pei Mingli to organize sales teams and seek out distributors to spread the stoves nationwide. Simultaneously, he arranged for the production of boilers and heaters, targeting the wealthy. The price for each set started at five thousand strings of coins.

This new venture at once caught the attention of Li Shimin. He had long wanted to take a stake in Li Zhi’s enterprises but had been too embarrassed to bring it up. Now, faced with such a lucrative project, he could no longer hold back. He summoned Li Zhi to the Hall of Supreme Harmony and, in an uncharacteristically gentle tone, said, “My dear child, you’ve invested in so many ventures—I imagine you don’t have much ready money left. I still have some; why not let me invest as a partner?”

Li Zhi instantly understood that his father was envious of his profits. And truthfully, as emperor, Li Shimin was so poor that even his harem had to scrimp and save—a pitiable state for a sovereign. Li Zhi would not let such a powerful ally slip away. He patted his chest and replied without hesitation, “Father, how can you say such a thing? Since you fancy my enterprises, I’ll give you half the shares—there’s no need for you to spend a single coin!”

Li Shimin waved his hand, “No, no, it’s not easy for you to do business. How could I take advantage of you for nothing?”