T H Huxley was known as ‘Darwin’s Bulldog’ for his support of the theory of evolution. But Huxley opposed the idea that ‘social Darwinism’ - the improvement of society by the survival of the stronger - would make for a more secure future for the human species. Huxley believed that it should not be beyond the power of human thought to work against the ‘cosmic process’ of combative evolution, and to apply the necessary correctives, including the restriction of population growth, for humans to survive. 

While a student the novelist H G Wells had attended Huxley’s lectures on biology and evolution at what was then (1884) the Normal School of Science. In his autobiography (1934) Wells rated Huxley with Darwin, and Plato, Aristotle and Galileo, while understanding that much of his work had by then been superseded. 

What happens scientifically in the last section of H G Wells's The Time Machine

The move towards entropy is described in the move towards end of the earth in Chapter 11 of The Time Machine. The second law of thermodynamics drives the description of the environment in this section – the whole earth has cooled down as the sun cools and the earth ceases to revolve, and in the next stage, thirty million years onwards, despite the size and proximity of the sun, there is ‘a bitter cold’. 

Was this prospect believed at the time of writing the novel? 

In his preface to the 1931 edition of the novel Wells wrote, 

… the geologists and astronomers of that time told us dreadful lies about the 'inevitable' freezing up of the world – and of life and mankind with it. There was no escape it seemed. The whole game of life would be over in a million years or less.

What specifically in Huxley’s work refers to the approach of entropy? 

This lecture, given in 1893, looks at various notions of Indian and Greek ethics within the framework of evolution. On page 32 Huxley considers the notion of ‘fittest’ which he points out has a moral flavour rather than a circumstantial application. In the environment of a cooling world the fittest organisms would not be human beings but ‘humbler organisms’ such as those which Wells envisaged in Chapter 11 of The Time Machine.