Wittgenstein, Ludwig and Russell, Bertrand.

4 lines of logical equations, two by Wittgenstein with corrections and two additional lines by Russell, written on the verso of a printed invitation to the opening of a bookshop at 5 All Saints' Passage, Cambridge, with, at the top of the recto, an autograph note signed by Wittgenstein, to G.E. Moore ("...I'm afraid that Russell and I took this from Mrs Moore's mantlepiece to scribble on & I then put it in my pocket & forgot it there..."), 2 pages, 8vo, the printed invitation dated 9 October 1935, in a green folding box

An evocative relic bringing together the three central figures of the Cambridge School.