Grant Allen, born Charles Grant Blairfindie Allen on February 24, 1848, was a noteworthy Canadian science writer and novelist, distinguished for his prolific contributions in the late 19th and early 20th centuries. Allen's breadth of interest spanned from science to literature, and he is well-remembered for his exploration of evolutionary theory in lay terms. One of Allen's significant scholarly works, 'The Colour-Sense: Its Origin and Development', is a seminal text that examined the evolutionary aspects of colour perception, reflecting his dedication to evolutionary psychology and biology - fields that were rapidly developing in his time, influenced by the works of Charles Darwin and Herbert Spencer. Allen was a prominent figure in the intellectual circles of his era, advocating for rationalism and social reform. His literary style combined intellectual rigour with an accessible narrative approach, allowing for broad engagement with his ideas. He studied at King Edward's School in Birmingham and later at Merton College, Oxford, where he developed his interest in science and literature. His other notable works include 'An African Millionaire', which displayed his versatility as an author, blending social commentary with entertainment. Allen's legacy endures through his insightful analysis of human nature and society, his contribution to scientific discourse on perception and evolution, and his influence on the transition of literature into the modern age.