One of the great mysteries of science is that underneath all the complexities of the universe is an underlying harmonious order, whose existence Einstein described as 'a miracle'. No less miraculous, the fundamental laws of the universe can be written in the language of advanced mathematics. Searching for these laws, physicists have found themselves developing ambitious mathematical ideas. Without observation and experiment as their guide are they now 'lost of maths' and doing 'fairy-tale physics' as their detractors claim? In The Universe Speaks in Numbers Farmelo argues that such criticisms are too pessimistic and shows that today's greatest scientific minds are working in a tradition that dates back to Newton. He takes us on an adventure from the Enlightenment, through to the breakthroughs of Einstein and Dirac, and all the way up to work of contemporary physicists and mathematicians who are shedding light on each other's disciplines to mutual surprise and great excitement. As Farmelo shows, this blossoming relationship between mathematics and physics could redefine reality as we know it and it is responsible for huge advances in our understanding of reality, space and time. Always lively and authoritative, Farmelo navigates the reader through the most thrilling and controversial developments in contemporary thought. This is essential reading for anyone interested understanding how physicists are attempting - in Stephen Hawking's words, to 'know the mind of God.'