The show is called Open/Closed, Big/Small, Full/Empty, On/Off. Plainly, it is about oppositions, four sets of them to be precise, set up by Scottish artist Martin Creed, a philosopher who likes to play. Big/Small shall be represented, for instance, by the co-residency, during gallery hours, of a Chihuahua and an Irish wolfhound, a dog that can stand taller than its owner when it gets on two feet. Another gallery will be full to half its height with silver balloons, to fulfill the artist's instruction: "half the air in a given space." And then some. Get over there and just live between things for a while. (Western Bridge, 3412 Fourth Ave S, www.westernbridge.org, noon–6 pm, free)