 The first known mention of the term was in the writings of the 5th-century BC Greek philosopher Anaxagoras.Panspermia began to assume a more scientific form through the proposals of Jöns Jacob Berzelius (1834), Hermann E. Richter (1865), Kelvin (1871), Hermann von Helmholtz (1879) and finally reaching the level of a detailed scientific hypothesis through the efforts of the Swedish chemist Svante Arrhenius (1903).Fred Hoyle (1915–2001) and Chandra Wickramasinghe (born 1939) were influential proponents of panspermia.