Read "Of Those Sentiments Concerning Nature with Which Philosophers Were Delighted" by Plutarch online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
The Stoics say that the stars are of a circular form, like the sun, the moon, and the world. Cleanthes, that they are of a conical figure. Anaximenes, that they are fastened as nails in the crystalline firmament; some others, that they are fiery plates of gold, resembling pictures.