A Meeting of Minds
Sean Nee, in his obituary of the great evolutionary theorist (and I mean theorist) John Maynard Smith (Trends in Ecology and Evolution 19: 345-6, 2004), retells his "favorite JMS story":
One day, Haldane brought a visitor to JMS’ lab and asked him to explain to the visitor the aerodynamic problem he was working on. JMS began going through the equations on the blackboard when the visitor’s hand reached out, grabbed some chalk and started correcting the equations. JMS asked, ‘Sorry, I did not quite catch your name?’. The visitor answered, ‘Alan Turing’.