In looking up more about Tim Hyman, I have now seen his statement on drawing on the Royal Drawing School’s website:-

My own principal reason for going out drawing is to renew my sense of space, of being in the world; if I stop drawing for several weeks, I find my spatial invention goes dead in my paintings, and my art becomes schematic. But I also draw because the specific – a friend’s face, a familiar London Street – has appeared before me as a moment of seeing, as an epiphany, to which I must somehow respond. As a teacher, I hope to transmit the instability and flux and surprisingness of visual experience – for example, the unmeasurable counterpoint of crowd and traffic, moving against the stillness of architecture. I can’t teach drawing as a “skill”, since I often flounder. Two favourite Bonnard quotations: Drawing is ‘The Transcription of the Adventures of the Optic Nerve’; and a definition of art – ‘Many little lies for one big truth’.