Edinburgh’s Collective is the most beautifully situated gallery in Britain, perched on top of Calton Hill with glorious views of Arthur’s Seat and the sea beyond Leith. Unfortunately every time I go there, the art is rubbish. Ruth Ewan’s Marxist cartoon The Beast lives down to this gallery’s sloppy standards. Andrew Carnegie, the Scottish-born industrialist who became one of the US’s richest philanthropists, is berated by his own dinosaur “Dippy”, the famous diplodocus whose skeleton he put on display in Pittsburgh while sending casts to museums around the world, including Britain’s Natural History Museum, as an ambassador of world peace. Ewan’s film has Dippy chastise a kilt-clad Carnegie for concealing his ruthless capitalism behind a generosity that included founding 2,509 libraries worldwide. That doesn’t wash with Dippy. “Turn to dust, Andrew Carnegie!” she urges. The animation is as crap as the argument is one-sided. Yet its theme of Scottish philanthropy is shared by the best show at the Edinburgh art festival, A Taste for Impressionism at the Scottish National Gallery, down on the Mound. This exhibition celebrates wealthy Scottish art collectors, notably Alexander and Rosalind Maitland, who bought masterpieces of modern French art and bequeathed them to the public. This may not sound like a recipe for excitement, even with its much-reported revelation of a hidden Van Gogh self-portrait on the back of a study for The Potato Eaters. But it’s an irresistible box of bonbons for the eyes with a few shots of absinthe thrown in. Advertisement Monet’s Haystacks: Snow Effect is a dazzling dream painting from 1891 in which silver and blue light reflected off snow turns two loaf-like haystacks into ethereal abstractions against a pink sky. Gauguin’s Martinique Landscape equals it in the abstract intensity of its reds and greens, cooking up a tropical heat that dissolves reality. This cavalcade of perceptual revolutions also stars Courbet, Millet, Pissarro and Cézanne, and a Degas bronze of a woman baring all in the bath whose explicitness has no peers today except Tracey Emin, whose nudes are at Edinburgh’s Jupiter Artland for comparison. It climaxes with Matisse’s Jazz. You see with new clarity how Matisse, in these 1940s prints that identify with African American music, expressed his hatred of nazism and belief in liberty: his ever-transforming cut-up colours shape and reshape impressions as spontaneously as a bebop solo. How do you follow that? Platform at the French Institute is billed as a stage for “emerging” Scottish artists but this leaves you wondering how they are to be judged – as students or fully fledged practitioners? There’s a sense here of artists being too cosily indulged, getting away with stuff that is slight. Perhaps Scotland needs nastier art critics. I like Lynsey MacKenzie’s room of pink, orange and yellow abstract paintings, windswept and cleansing – yet she needs another dimension, some harder thinking to make them great. Then again perhaps this loss of purpose and energy in art is a worldwide phenomenon. At the Talbot Rice, the kind of weirdly arbitrary space that makes you wonder why anyone thought it would make a good art gallery, a survey of London-based Céline Condorelli raises a worry if anyone is imposing quality control anywhere now. Condorelli’s installations include plants and celebrate playgrounds as well as Brazil’s modernist architecture. I seem to have seen that a hundred times before. Vague semi-comprehensible utopian rhetoric is mixed with collections of found objects and cocktails of colour that don’t have any emotional resonance. This is art that exists only for someone to write a thesis about it. You can see art that lives and breathes at Stills, a photography centre surrounded by tourist cafes on a street curling down from the Royal Mile, where Japan’s Ishiuchi Miyako has a small but shattering retrospective of her shockingly intimate photographs. Going through the gallery’s shopfront entrance you find yourself surrounded by frayed and torn yet exquisitely colourful clothes: a blue and white suit that’s been savagely ripped up, lacy dresses that look charred as well as gnawed by giant moths. What makes these photographs so uncanny is Ishiuchi’s perfect lighting and colour, which you feel she must have spent months getting just so. And then you realise what they are. These are the clothes of victims of the atom bomb dropped on Hiroshima in 1945. It takes a serious artist to expose a genuinely fresh perspective on such a tragedy, but these eerily beautiful pictures make you see the horror as if for the first time – the clothes blasted apart in wardrobes or torn and burnt off bodies, their frail delicate, fashions still bearing witness to all the variety of lives that were stilled in a moment. Ishiuchi brings the same unsettling intimacy to pictures of her late mother’s possessions and Frida Kahlo’s medical corset, seemingly able to get her camera inside the objects, to touch ghosts. Down the hill at the Fruitmarket Gallery there’s further proof that art can escape the corset of ideological curating to express something about being alive. Daniel Silver has created a bonkers world of ceramic people, thrown together with wild, hilarious sloppiness then painted in head-spinning colours. Small figures are spread out on tables with huge clay human legs and an “audience” of grimacing faces stare back at you, while random giant legs occupy a third space of their own. Silver’s people should be absurd, like Carnegie and his dinosaur. But the difference is empathy. His clay faces and bodies may be ridiculous – but have you looked in the mirror lately? We are they. Each of these vulnerable, isolated beings is an expressionist portrayal of human existence. Silver echoes Auerbach and Baselitz, and they are among the best artists to echo. There’s real depth at this art festival, and even the sillier stuff is, after all, an excuse to explore one of Europe’s most remarkable cities. Don’t miss Dovecot Studios, near the South Bridge, where you can watch weavers at work as well as seeing a retrospective of the late Scottish modernist Alan Davie. At the time of his death in 2014 the nonagenarian Davie couldn’t have seemed less relevant. Yet this exhibition confirms him as an artist of biting power, Scotland’s Jackson Pollock, who kept the flame of abstract art ablaze in a Britain that had little time for it. Art either has guts and vision or it doesn’t, and the rough spattery paintings of Davie have it in peat-cutting spades.