From Richard Cragg
Thank you for Regina Peldszus's review of Samuel Arbesman's book warning that we have reached the stage where very few “experts” really understand the complexity of the software systems they have installed to control critical parts of our infrastructure (23 July, p 42). This reminds me of the lament of Nobel laureate Eugene Wigner: “It is nice to know that the computer understands the problem. But I would like to understand it too.”
London, UK
