I was apprehensive about visiting the RA’s recent exposition of Abstract Expressionism (or ‘Ab Ex’ as they rather trendily called it). An art form which avoids solidity of interpretation at all costs seems fertile ground for pseuds. I could just see them in their berets standing in front of meaningless splodges, musing over adjectives like “gritty” and “dispossessive”. The exhibition publicity campaign did little to allay my fears: a particularly impenetrable section from a Jackson Pollock painting overlayed with the command Experience Abstract Expressionism. No, I don’t want to experience anything; I want to know what these random squiggles mean! Still, given that this was allegedly one of the most important art movements of the twentieth century, I though there must be something to it. So, off I toddled to Leicester Square, hoping to be impressed. And, to some extent, I was.

The Royal Academy’s traditional introductory display was, as usual, excellent. A series of abstract David Smith sculptures stood outside in the court, arranged so that their respective forms seemed to respond to each other. Though abstract, these pieces were undeniably appealing. Nevertheless, they were still clear, sold blocks of reality, tangible even to the most obstinate viewer, and I didn’t feel they expressed very much. It would take me more of this to prove Ab Ex’s validity.

The first room covered early or transitional work by the artists under examination – mostly moody portraits and dark, nightmarish compositions. The focal hanging was clearly Pollock’s Male and Female in which Picasso’s influence was unmistakable and the exposition of ideas accessible. I felt just about at home here. David Smith’s Letter sculpture displayed in the centre was truly brilliant. He drew the form of a handwritten letter into the third dimension through consistent yet grotesque twists of metal, which succeeded in making the familiar thoroughly strange.

Then the problems began. The next display concentrated on Pollock’s later revolutionary ‘pouring’ technique in which paint is splashed onto the canvas from a height. These, along with Franz Kline’s black streaks intermingling with a white background, might be described as Action Art. In this field, striking as these works were, I confess that I found little value. The marks function supposedly as frozen performance pieces, not representing anything ‘physical’, but rather, like a long exposure photograph, a snapshot of the artist’s gestures during composition. Artistic self-referentiality is all very well, but it only seems justified if you’ve got something interesting to say through the work itself, otherwise the artist identifies him/herself as the most important thing in the artistic process and becomes utterly self-absorbed.

I soon realised that my favourite work so far, de Kooning’s Pink Angels, had been painted as a reaction to an earlier, thoroughly representative, work by Titian. The two Pollock paintings I liked the most – Mural and Blue Poles, also his most famous – were his most representative, overlaid with recognisable imagery. I was deriving much more enjoyment from works grounded in something figurative I could latch onto: disembodied parts of the female form, shadowy striding figures, even a series of blue sticks – just give me something! I was becoming less and less convinced of the value of abstraction.

But in the Rothko room, I had an epiphany. His richly coloured rectangles were undoubtedly some of the most abstract in the exhibition, yet I felt totally engaged emotionally and intellectually. His work wasn’t grounded in external reality; it created its own reality, held together by consistency of form. Accessible at first sight, the colours of his shapes were layered to give them an ethereal, almost holy quality. If you’ve never had the opportunity properly to contemplate the word façade, I suggest doing so in front of a Rothko painting. He reduces concealing and revealing to a single instant, expressed in the simplest of terms.

Moving to view other ‘colour field’ artists Reinhardt and Newman, I went from strength to strength. Pollock’s early Male and Female now felt positively clumsy compared to Newman’s deceptively intricate Adam and Eve pair. Where Pollock had used straight lines for the Male and curvaceous for the Female, Newman in Eve had reversed Adam’s colour emphasis. Newman had played with multiple meanings of Eve through an expert manipulation of focus and drew on the etymology of Adam in his colour scheme; Pollock had resorted to writing mathematical symbols on the Male figure and put the Female’s eyes on sideways – revolutionary? Hardly.

This exhibition brought me a long way towards understanding Ab Ex as a cohesive movement. I would have been totally lost without the audio-guide. It provided, for example, the personal history to transform Joan Mitchell’s Mandres from a messy splurge into an emotionally effecting piece. I was also generally convinced by the arrangement – broadly by artist, which seems the only sensible away to approach such a range of styles. Unfortunately, there were many riveting pieces, such as Mark Tobey’s Parnussus, displayed less prominently and glossed over in the commentary because they weren’t by the principal figures of Ab Ex, in the RA authorities’ view (a distinction at which I feel sure the artists themselves would have balked). The attention they devoted to the generally sidelined Clifford Still was, however, thoroughly justified. His sublime and expansive pieces defied deconstruction or analysis.

As to the movement itself, I found Ab Ex most successful when it reduced art to its bare essentials, leading to an exploration of how daubs of colour allow an artist to communicate states of mind to a viewer. This exhibition made me realise that to limit the artist’s means to ‘depiction’ would be greatly to inhibit the visual arts. My initial misgivings perhaps arose because it is difficult to come to terms with something which does not clearly signify anything, yet whose significance is undeniable.