In two cities this summer I have seen two extraordinary spaces, one temporary the other permanent, created by two artists who, though separated by time and place, are similarly capable of transporting the viewer into the mysterious world of reflections.

Housed in the Orangerie, Monet’s waterlilies, floating on flat reflective surfaces, invoke a mood of tranquil, even passive, reflection; while Eliasson deploys the raw mechanics of reflection – mirror, light, surface – to invite our active participation in the spare galleries of the Martin-Gropius-Bau.

Monet opens up a fathomless space in his long curved passages of air and water. Eliasson opens up space within the fabric of the building designed to contain it. Both hold up a deceptively simple mirror to the viewer, opening up in the process an immersive space that becomes a temporal experience, something that generates in the act of perceptual disorientation a fresh engagement with our own state of being, rather than something which requires the decoding of a singular image or the recovery of a particular meaning.

There is perhaps, in their treatment of time and scale, a difference in degree. With Eliasson, the viewer’s body – its primal movement through fields of coloured light and fog – recasts the familiar (this space, my body) in strange and unfamiliar ways. With Monet, it is the eye, simultaneously gazing across and into the aqueous expanses of light and dark, lost in momentary emptiness before returning to the surface with brilliantly coloured gestural marks, that carries the mind through deep and silent territory. Reflections in water, like Eliasson’s mirrors, that move as we move, in endless permutations. Visual fields which both reveal and complicate our presence, and which give substance to time and space, our own as well as theirs.

Monet’s Waterlilies are on permanent display in the Orangerie, Paris.

Olafur Eliasson’s exhibition, Inner City Out, is at the Martin-Gropius-Bau, Berlin, until 9 August 2010.