He is Tintin's friend, an absent-minded professor and half-deaf physicist, who invents many sophisticated devices used in the series, such as a one-person shark-shaped submarine, the Moon rocket, and an ultrasound weapon.

Calculus first appeared in Red Rackham's Treasure (more specifically in the newspaper prepublication of 4–5 March 1943[2]), and was the result of Hergé's long quest to find the archetypal mad scientist or absent-minded professor.

Although Hergé had included characters with similar traits in earlier stories, Calculus developed into a much more complex figure as the series progressed.

Calculus is a genius, who demonstrates himself throughout the series to be an expert in many fields of science, holding three PhDs in nuclear and theoretical physics, and planetary astronomy.

Many of his inventions precede or mirror similar technological developments in the real world (most notably the Moon rocket, but also his failed attempt at creating a colour television set).

However, after completing the journey to the Moon, Calculus discarded his hearing aid, forcing his friends to readjust to his hearing impairment (aside from one panel in The Castafiore Emerald, when Tintin is seen speaking to him through his ear-trumpet); this restored the humour surrounding him, though it could be that he finds his deafness useful since it enables him to focus on his work (something useful for The Calculus Affair, since he was referencing ultrasonic sound).

He is fairly protective of his work, on occasion hiding his scientific endeavours from Tintin and Haddock (which gets him into trouble in The Calculus Affair).

On an earlier occasion, during his efforts to find an antidote to Formula Fourteen in Land of Black Gold, Calculus almost destroyed half of Marlinspike in an explosion.

Another occasion is in Flight 714 to Sydney when, due to some misunderstanding, he physically assaults Laszlo Carreidas and has to be held back with great effort by Haddock and Tintin.

Haddock invited him to stay at Marlinspike Hall after Calculus discovered it is the captain's ancestral home and bought it in his name thanks to money he had earned through selling the patent for his shark-submarine.

"[3] The Swiss physics professor held a teaching appointment in Brussels when Hergé spotted his unmistakable figure in the street.

Philippe Goddin has suggested that Calculus' deafness was inspired by Paul Eydt, whom Hergé had known at Le Vingtième Siècle where Tintin's adventures had first appeared.

He works with Mr. Baxter and Frank Wolff on the Moon rocket and corresponds with ultrasonics expert Professor Alfredo Topolino of Nyon in The Calculus Affair.