If Frank Gehry's Guggenheim Museum is a piece of architectural sculpture, it also serves well as an architecture for the display of sculpture and it is hard to imagine two exhibitions which could make better use of its spaces than those currently on show.
In the international stakes, Richard Serra is probably some way ahead of Eduardo Chillida, although both have had generous showings in London in the 1990s. Serra's work, a group of pieces previously in Los Angeles County Museum, is exhibited at Bilbao in a single space - the long gallery with curving walls and roof which forms the southern arm of Gehry's museum, whose fish-tail tickles the underside of the road bridge across the River Nervion.
With Serra, you get what you see, and you know in advance what it will be, but there is still an indispensable quality of physical engagement with the work: walking into the constricted spaces between his walls of rusting steel, being thrown off balance by the loss of a true vertical, and admiring the patina of close-grained orange-on-brown which encloses you. The other spectators become part of the entertainment, so that these apparently minimal pieces start to work in a variety of ways.
One triple serpent of steel, appropriately called Snake, runs down the middle, flanked by clusters of Torqued Ellipses, each disclosing a slightly different experience. It could hardly be purer or more concentrated, but is it mania or academicism that demands so unvarying a visual language?
The Chillida show is a retrospective of work between 1948 and 1998, filling a sequence of galleries. It includes stone sculpture, welded iron, and works on paper (drawn, printed and constructed).
Chillida comes from nearby San Sebastian and, as a student in Paris, realised that the genius of the Basque country is embodied in its 'dark light' and in the qualities of iron. He works with symbolic aspects of form which lie almost too deep for verbal explanation. As with Henry Moore, you can see it without having to ask about it, although his 'subject matter' is quite unlike Moore's and his sculptural methods are more direct.
Gaston Bachelard wrote in celebration of Chillida's work, and the artist collaborated with Martin Heidegger on illustrating some of his texts. This concern with depth of meaning brings Chillida close to current issues in architecture, such as materiality and 'being in the world'. He is overtly mystical in some of his utterances (but never pretentious), and his words are on the walls and in the excellent audio guide.
If Serra's work achieves a comfortable fit in Gehry's galleries, then Chillida's does something more, providing a commentary and explication in visual form and in words. The Guggenheim has been received so far more as an architectural sensation than as a work of profound thought. Without declaring which it is, Chillida encourages a reading of the building that dignifies and deepens it, making it a kind of echo chamber for the ideas on show.
There is Chillida's interest in things being off vertical and horizontal, something shared with Serra and with the architecture. Although architectural theory is still trying to work out what this deviation means, Chillida explains that, while the Greeks discovered the right angle as 'the angle that man makes with his shadow', its formulation at precisely 90 degrees might have been 'a late rationalisation'. When allowed some variation, it becomes 'a living angle'. (Gehry's building is off vertical to a greater extent than this, but perhaps it is the first wild breakthrough to a post- rationalist architecture which in future need not shout so loudly.)
Moreover, there is the regional aspect, whereby Gehry's combination of metal and stone facings to the outside of the building is echoed in Chillida's own palette of materials. Gehry has understood the 'dark light' both literally and, I would suggest, metaphysically in his tender embrace of the irrational. This adds up to a great deal more than 'keeping in keeping', but it does that too.
Alan Powers is an architectural historian