This stark white cube is the home that philosopher Ludwig Wittgenstein built for his sister, Margaret Stonborough in the 1920s, together with the architect Paul Engelmann, a student of Adolf Loos.

The house demonstrates Wittgenstein’s rigorous philosophy, transposing into an architectural vocabulary his will for clear, concise and simple form. Wittgenstein appears to have been completely consumed with every detail of the plan, reportedly spending a year on the design of the doorknobs, and another on the radiators.

Wittgenstein’s relentless dismissal of ornament was very much indebted to the work of Adolf Loos, whose uncompromising aesthetic Wittgenstein greatly admired. Having inherited a huge fortune upon his father’s death in 1913, Wittgenstein had made the architect’s acquaintance when he donated a significant portion of those assets to support needy artists.

The Wittgenstein house was “Aryanized” during the Nazi period. Margaret Stonborough managed to recover the house after the war, but its furnishings had been largely dispersed. In the 1970s, the building was sold to the Bulgarian state and now houses the Bulgarian Cultural Institute.