I must admit that I enjoy killing things and, since the target of my murderous instincts are clothes moths, fruit flies and, occasionally, rats or mice, society condones my bloodthirsty instincts. But while I get some satisfaction from my exploits, the women in Paula Rego’s drawings and prints appear to go about their murderous business with a mixture of resignation and detachment. These things have to be done, their world-weary faces seem to say, let’s expedite them with as little fuss as possible.

It’s not often you find yourself in an art gallery with the business end of a bullwhip whizzing inches from your nose. Wielded by a disconcertingly slight, black-haired woman who can barely be half its length, the terrifying instrument defines the dimly lit space with its whirling undulations and earsplitting crack, sending the gaggle of spectators cowering into adjacent rooms. Why there is also a grand piano present is probably only entirely known to the unnamed artist who brought this trickily titled exhibition into being.

What a troubled life Alice Neel led. The death of her first child, a daughter, who died of diphtheria in 1928  just before her first birthday; another daughter lost to her estranged husband’s family in Cuba two years later (as an adult and a mother herself, the daughter, Isabetta, committed suicide); life as a single mother raising two later sons on welfare in the slum district of New York's Spanish Harlem; and a neglected but always diligent artist for much of the rest of it, only achieving fame and acclaim towards the end.

It takes a lot of work to make a show look as unconsidered and chaotic as this one: thought and care and time and attention all have to be paid before something so random can be achieved. But as so often with Tillmans, the nagging questions persist: is randomness, are the offhand and the casual, valid as ends in themselves? Because Tillman’s über-hip affectless cool has become very tiresome indeed. Even worse, it’s becoming predictable and dull. Tillman's eye, as ever, remains wonderful, but I remain doubtful about the form in which he chooses to convey his ideas.

It took Picasso four years to learn to paint like Raphael, but it took him a lifetime to paint like a child, or so he said. For Brancusi it wasn‘t a case of relearning childhood, but of being careful not to lose it in the first place. “When we are no longer children we are already dead,” he said.

In 1994, Francis Alÿs joined the regular hiring-line in the central square in Mexico City. Standing next to plumbers and carpenters with their hand-lettered signs touting their skills, his sign read "Turista", as he offered his ability to be an outsider looking in. Three years later, he returned to the square, the centre of city life, and the site of the annual Independence Day parade, and the "Grito de Dolores", the patriotic ringing of the bells at the National Palace which up to half a million people attend.

The gallery has been turned into a little girl’s dressing-up closet. The walls are painted midnight blue and dusted with glitter. Ballet shoes, made for small feet, and a discarded tutu are to be found in a decorous pile on the floor. There are shiny trinkets and princessy things and pictures of ballerinas in bright, pastel shades. And miniature cabinets, almost empty but for one or two small objects – old, discardable things that might be hoarded away as treasures by a child wrapped up in its own imaginary world.