Irene Roswitha Heim (born October 30, 1954) is a linguist and a leading specialist in semantics.
Heim's parents were German speakers born in Czechoslovakia, who had emigrated to Germany after World War II.
After short-term postdoctoral positions at Stanford University, MIT, the University of Texas at Austin (1983-1987), and UCLA, she took up a faculty position at MIT in 1987, receiving tenure as an associate professor in 1993 and becoming promoted to full professor in 1997.
In the second chapter of the work she argued (developing an insight by the philosopher David Lewis) that indefinite noun phrases like a cat in the sentence If a cat is not in Athens, she is in Rhodes are not quantifiers but free variables bound by an existential operator inserted in the sentence by a semantic operation that she dubbed existential closure.
In 2010 Irene Heim was awarded a Senior Fellowship of the Zukunftskolleg at the University of Konstanz.