It's more than just Heart and Soul: the Berkeley Arts Festival presents an evening of four-hand piano pieces, composed by beloved local minimalist Terry Riley, and performed by Joseph Kubera and Berkeley radio host/pianist Sarah Cahill. 8 p.m., $10-20 sliding scale, at the temporary Berkeley Arts Festival location, which is the Fidelity Bank Building at 2323 Shattuck (x Bancroft). Other events: --A talk at the SF Main Public Library on "How to Listen to......