The easiest mistake to make in appreciating George Condo would be to assume that his manic style reflects a manic creation or a manic practice. Some of Condo's paintings and drawings, with their childlike loops and gurning, disfigured faces, look like he made them in a fit of violence or some hysterical trance, but the real surprise of two new shows at the Hayward Gallery and at Sprüth Magers in Mayfair is the care and the calmness that lies behind them.

Art about art is one of my favourite kinds of art. Paintings, drawings, sculptures, films - works of art which talk about what art is, what the image is, what art can represent and what it can't - all appeal. It is not just a picture of some prostitutes and some African masks - it is Les demoiselles d'Avignon by Picasso and it blows apart the boundaries of painting by cramming three dimensions into two. And then there is Frank Stella, in a new survey of his career at Haunch of Venison, the ultimate modern artist-about-art - and I'm left cold.

Simon Starling’s wonderfully eccentric exhibition Never the Same River (Possible Futures, Probable Pasts) will inevitably mean more to those who have visited the Camden Arts Centre regularly over the years. Places gradually acquire a patina of memories that accumulate layer on layer and infiltrate one’s perceptions in the present moment. Travelling round London, I encounter my past at every corner – the Slade where I spent many hours drinking coffee before being gripped with ambition to become an artist, University College Hospital where I gave birth, the house where I discovered how hard it is to be an adult, the doorstep on which a former lover confronted a future one, and so on.

Derek Jacobi (b 1938) grew up in Leytonstone. His father was a tobacconist, his mother worked in a department store. Although he entered the profession in the great age of social mobility in the early 1960s, no one could have predicted that he would go on to play so many English kings - Edward II, a couple of Henry VIIIs and Shakespeare’s two Richards - as well as a Spanish one in Don Carlos. This month he prepares to play another king of Albion: Lear, against which all classical actors past a certain age must finally measure themselves.

The Celtic Tiger ran rampant through Ireland during the boom years of 1995-2007 when national institutions expanded their collections, galleries popped up and collectors, buyers and artists had a rare time. With literature, the new young Chick Lit writers made their mark, sometimes even outselling the serious contemporaries, and Seamus Heaney rightly got a Nobel Prize. With the crash, prices in Dublin’s major art auction houses fell by 50 per cent as the blinged-up property developers froze; if they did buy, they shifted from contemporary to reassuringly Irish "genre paintings" of peasants in rural landscapes and thatched cottages by the sea.

Multiple images of silhouetted horses cantering against blank backgrounds in grids of movement are what most people associate with Eadward Muybridge. Made in the late 1880s, they have contributed to his lasting reputation as a pioneer of photography and the moving image. So it is astonishing to discover through Tate Britain’s magnificent exhibition of his life’s work, that horses were only part of a story packed with surprises.