  The answer to the question in the title of Brouwer’s paper “Does Every Real Number Have a Decimal Expansion?” (1921A) turns out to be no. Brouwer demonstrates that one can construct choice sequences satisfying the Cauchy condition that in their exact development depend on an as yet open problem. No decimal expansion can be constructed until the open problem is solved; on Brouwer’s strict constructivist view, this means that no decimal expansion exists until the open problem is solved. In this sense, one can construct real numbers (i.e., converging choice sequences) that do not yet have a decimal expansion.