Should current events leave you unexpectedly at a loose end, allow me to point you in the direction of Sol LeWitt's excellent short essay on Conceptual art, which he wrote for Art Forum magazine in 1967.
I think it is possibly the best article ever written concerning a notoriously slippery art genre, about which LeWitt knew a great deal, as he himself was a Conceptual artist (he also wrote well, with a lively style that pulls you through the more arcane passages).
As the name implies, Conceptual art is all about the idea, its physical realisation being secondary: the concept is the artwork, not the object.
This can mean, for anyone in the market for piece of Conceptual art, there's a very real risk of going home with a scrap of paper on which a set of instructions have been scribbled (because the idea is the art), rather than its representation in a splendid sculpture or painting.
It's like a trip to Ikea, but there's no flat-pack kit.
It is said, possibly apocryphally, that a very famous contemporary artist adopted the same approach when it came to paintings produced by his assistants following his style-guide.
He would sign the finished canvasses and date them with the year he came up with the idea for the composition, not the year they were painted by an assistant.
The upshot of which, apparently, was that he ended up signing artworks with a date before the person who actually painted the canvas was born.
And so it goes with Conceptual art, which has been on my mind this week following a trip to the Yorkshire Sculpture Park to see the newly installed monumental artworks by Portugal's Joana Vasconcelos, who describes herself as a Conceptual artist.
It is fair to say her work is the polar opposite to LeWitt's in terms of aesthetic.
He wanted to take art back to its bare essentials, with his cool monochromatic wall paintings and austere geometric sculptures.
Vasconcelos, on the other hand, is all about vibrant colour and baroque kitsch.
I suspect her massive cockerel (Pop Galo, 2016), which you encounter as you enter the park, would have appalled the late American artist.
The lively collection of ceramic tiles and LED lights covering its body would have been bad enough, but the music emanating from it would have tipped him over the edge.
"Too much!" he'd say while making a beeline for James Turrell's beautifully minimalist Deer Shelter Skyspace, in which you sit against a concrete wall and look up at the sky through a rectangle cut in the roof.
LeWitt was forthright about the elephant traps awaiting Conceptual artists.
Gigantic, colourful, expressionistic artworks were at the top of his list of no-nos.
"When the viewer is dwarfed by the larger size of a piece this domination emphasizes the physical and emotive power of the form at the expense of losing the idea of the piece.
"New materials are one of the great afflictions of contemporary art. Some artists confuse new materials with new ideas. There is nothing worse than seeing art that wallows in gaudy baubles."
That's not how Joana Vasconcelos sees it.
She works with whatever materials are demanded by her concept, which might have gaudiness at its heart.
Solitário (2018) is a 7m (23ft) high wedding ring made out of gold-alloy car wheel rims topped off with a stack of whisky glasses shaped like a diamond.
It is tasteless in the extreme.
A vulgar blot on the landscape, framing the bucolic Yorkshire countryside with a crassness that seeks to comment on our age of rabid materialism.
That is the artist's intention, gaudy is her concept.
A different idea calls for different materials.
I'll Be Your Mirror (2018-20) is a sculpture about identities and perception.
It consists of a series of overlapping, gilded, two-side mirrors arranged into the shape of a huge Venetian mask (an artwork that has taken on added meaning with the advent of Covid-19). It's not exactly subtle, but what's wrong with being direct?
Conceptual art doesn't have to be a puzzle.
But it needs layers that take it beyond a static one-liner, which this work does both literally and metaphorically.
That cannot be said for all the works on display in this outdoor/indoor exhibition.
An oversized ice cream cone called Tutti Frutti (2011) is underwhelming. Vasconcelos has made it from children's plastic sand moulds of apples, pears, croissants and strawberries.
It isn't very interesting to look at, and the concept (sugary seduction, greed, and hollowness) is laboured.
The same can be said for Marilyn (2011), a giant pair of stilettos created out of stainless-steel saucepans, for which no explanation is needed.
Her best work is the gallery-filling Valkyrie Marina Rinaldi (2014), a biomorphic goddess covered in the materials from the fashion house Max Mara, with whom the artist was collaborating.
It clearly draws on Louise Bourgeois's knitted figures and Niki de Saint Phalle's extravagant, blobby women - but it has its own heart and soul: not least its joyful celebration of all those materials and associated crafts about which LeWitt was sniffy.
I think there is room for an expressionistic artist like Joana Vasconcelos in the Conceptual art club.
Ideas can have feelings.
But LeWitt is spot on with much of what he says, particularly in his pithy summation to his essay: "Conceptual art is good only when the idea is good."
Vasconcelos's Instagram-friendly art is full of good ideas but lacks any great ones.
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