A famous etching by Swiss-German artist Paul Klee, titled Rechnender Greis (Old Man Calculating), depicting a bald, elderly man counting on his fingers with expressive, wavering lines, capturing themes of ageing, life's brevity, and mental activity.

Artist: Paul Klee (1879–1940).

Date: 1929.

Medium: Etching.

Subject: A humorous yet poignant portrayal of an old man, characterised by his bald head and toothless smile, using his fingers for arithmetic.

Style: The rough, irregular lines from the etching process add to the sense of mental effort, fitting within Klee's diverse, hard-to-classify work (Expressionism, Bauhaus, etc.).