"The more specific idea of Evolution now reached is - a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter"

Herbert Spencer's quote is referring to the concept of evolution as a procedure of change from a state of homogeneity to a state of heterogeneity. Homogeneity is a state of uniformity, where all aspects are the exact same, while heterogeneity is a state of diversity, where aspects are various. Spencer is recommending that evolution is a process of modification from a state of uniformity to a state of variety, which is accompanied by the dissipation of movement and combination of matter. This recommends that development is a procedure of change from a state of mayhem to a state of order, where matter is arranged and motion is dissipated. This idea of advancement is supported by the scientific evidence of the development of life on Earth, which has seen the emergence of progressively intricate and diverse forms of life in time.