Brunello Cucinelli, a stubbly 63-year-old son of a cement-factory worker, squeezes my shoulder, inhales deeply, and observes: “Bella.” In the shallow Umbrian valley beneath us sits a Palladian villa surrounded by vines, parkland, soft green fields, herb gardens and houses with yolk-yellow terracotta roofs. Over to the right, the large, L-shaped factory barely detracts from the bucolic panorama.

This is the view that Cucinelli built – along with the painstakingly restored 14th-century hamlet of Solomeo. Swallows call from the eaves of Cucinelli’s oversubscribed craft school, where this year’s students of tailoring, stonemasonry and embroidery, among other disciplines, are winding down for their 90-minute lunch break (all 1,060 workers here are encouraged to take one). Before heading down the hill to join them in the subsidised staff restaurant, which serves locally sourced vegetables, pasta and vitello al tonno, we contemplate a bust of Kant below which is inscribed – in Italian – a shortened version of the philosopher’s “perfect duty”: “Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.” Nearby is Solomeo’s theatre, free to all comers, where on the following Saturday Isabelle Huppert will be reading from Maupassant.

Cucinelli founded his company in 1978 as a one-man operation selling brightly coloured, Benetton-inspired cashmere sweaters. He began buying up Solomeo, his wife’s birthplace, in the mid-1980s. Today it is the symbol of “humanistic capitalism”: Cucinelli pays his staff more than the average wage for their jobs, insists they work no longer than eight-and-a-half hours a day, and spends around 20% of his profits on what he calls “the gift”. Past “gifts” have included the restoration of historic buildings razed by the earthquakes that keep assailing this part of Italy. Showing me around the fountain-flanked factory, Caroline, Cucinelli’s younger daughter, tells me that 85% of the firm’s products are made in Umbria, and the rest elsewhere in Italy.

Her father strides up to join us, and within ten minutes has mentioned Lorenzo de’ Medici, Ruskin, Rousseau and Adam Smith – all part of the pantheon of inspiring figures he says he imbibed through the books he read in a Perugian bar after dropping out of engineering school. He waves at the wide windows and the glorious view they look out on. “When we bought this place – it is an old garment factory from the Seventies – it had no windows. They were making high-level womenswear here but they did not want to spend 1% of their profits on windows! So we opened it up. It’s like Rousseau said: human beings are creative only when the environment around them is in harmony with creation…and John Ruskin – what a genius! If you look out the window and see something inspiring you will be inspired.”

Solomeo’s airy manufacturing space is used predominantly as a rapid-response unit to create samples of new garments designed by the on-site creative teams, or to fine-tune existing ones. Some staff painstakingly attach pre-knitted segments, thread by thread, onto the teeth of linkers for rammaglio – the tricky art of combining knitwear into the sum of its parts. A cluster of women – one of whom is a new graduate from craft school and, like all the students, has been offered full-time employment – gently insinuate by hand soft golden yarn into sweaters and cardigans. Others flatten panels of fine-gauge knit against backlit screens in search of even the tiniest flaw that will see them rejected.

For the dedicated neophyte, Cucinelli’s clothes might not be the most exciting. With the exception of the strafing of sugar-grain-sized crystals that sometimes trim the necklines, hems and ties on his women’s garments, bling is a rare thing here. Cucinelli measures the seasonal changes in his men’s jackets in millimetres, and has never indulged in celebrity endorsement (although he’s proud that Prince William wears his clothes). Instead of a catwalk show in Milan, he hosts a presentation at which buyers are encouraged to feel the quality of his merchandise. “I believe that’s what the entire world wants,” he says. “Whether it’s a Swiss watch or a British car or Italian clothes, they want quality and they want to know a lot of work and a lot of skill has gone into its manufacture, and they want to know that nobody has been hurt making it.” Like his philosophy, Cucinelli’s aesthetic is drawn from a classical canon. His soft tailoring, grey flannels, saddle shoes and shearling outerwear all rank in my experience as the Platonic ideal of their forms.

Capitalism and Kant don’t always go well together, and pleasing the stockmarket isn’t Cucinelli’s priority. His ideal growth rate, he says, is 10%: “the hedge funds aren’t interested in that but the pension funds are…we want only a smooth growth level. It must be gracious. Everything in this business has to be gracious. Profit is the gift when creation is perfect.”

But Cucinelli’s investors have nothing to complain about. He floated his company in 2012, presenting the chief executive of the Milan stock exchange with a 16th-century edition of Aristotle’s “Nicomachean Ethics” on the day of its initial public offering. Since then, his shares have tripled in value; in the same period, the Dow has risen by around a half. Quality tells.