Mario De Micheli, one of the most respected art critics in Europe, is also the author of several influential books on the history of art. His work has been translated and published in various countries in and outside of Europe. In 1998 De Micheli writes of Hagtvedt:

Hagtvedt is a 27 years old Norwegian: notably young for an artist so rich with experience. The tradition fathered by Munch, who died in 1944, is certainly evident. One must say that the colour and stroke of these canvases bring Munch to mind. Still, Hagtvedt is a curious painter, traversing at least two score countries, studying and occupying himself with every expressive element. In Italy (for the most part Florence) he has remained for an extended period of time, and it is here that I have become acquainted with his work.

It is, however, not easy to define Hagtvedt. He works with a severe chromatic intensity through which he manages to communicate the drama of his "protagonists". His reds and greens have a vehement and profound quality, and he is always concerned with the painful character of mankind as it confronts the problems of life. His images emerge from a darker background which renders them all the more effective. The situations in which we find ourselves implicated, create the circumstances of our discomfort and anxiety.

The men and women which Hagtvedt paints, his male and female portraits, belong to an alarmed universe where the spiritual tension arouses in us upsetting agitation. This is why he transmits such restlessness. Through every figure of his "repertoire", he composes and verifies the concrete truth of his fantasies.

While exploring himself, Hagtvedt's will manifests itself with resolute determination. He uninhibitedly reveals the substance of his visions, of his creative inspiration. The grave sentiment of our generally unhappy fate undoubtedly lies at the root of his worries, and he announces this as surely as we suffer. But what matters is Hagtvedt's capacity to represent such unhappiness in his works, not through abstract panic but through the certainty of concrete imagery.

Without a doubt, this is what particularly distinguishes Hagtvedt. Through his images, he revives the sense of both reality and symbolism. This sense enables him to present his discourse in a different manner, while the obligation of being faithful to himself is still maintained.