This article argues that although we have come to think of Virginia Woolf’s famous essay as a feminist manifesto, A Room of One’s Own (1929) is actually groundbreaking not in its call to action (as it is too vague, noninstructive, and disconnected to be anything of the kind), but in its refiguring and plumbing of the very idea of speculation. To speculate does not mean to be circumspect or to hedge one’s bets. Instead it is a forceful and simultaneously open-ended (and open-minded) process. This kind of force, rather than the force of prescription and pronouncement, gives the work its traction. This article reads Woolf’s work in the light of recent scholarship in the area of counterfactuals by Andrew H. Miller and firsthand accounts from Girton and Newnham undergraduates who attended Woolf’s original Cambridge lectures.