Proč slunce svítí a hřeje? Immanuel Kant: Oheň pouze na povrchu

The essay presents a lesser-known area of Kant's early work, when the philosopher was engaged in natural philosophy. Kant's reflections on the nature of the Sun are analysed, particularly from Universal Natural History and Theory of the Heavens (1755) and from the short essay Succinct Exposition of some Meditations on Fire (1756). In the first work, he deals with the origin and nature of the Sun, focusing primarily on what "fuel" the Sun burns and why it has not yet burned out, thereby answering the question "why does the Sun shine and heat?" He presents hypotheses about combustible light substances on the surface, the supporting role of air, and air-filled cavities inside the Sun. In the second work, these ideas are linked to his original theory of fire, which connects fire, heat, light, and aether into a single elastic substance.