Other philosophers say, and with great plausibility, that the spots, or at least the greatest part of them, are not newly produced, and then destroyed after a certain time; but large, solid, masses, of irregular forms, always subsisting; sometimes floating on the surface of the sun, sometimes partly, or entirely buried in the liquid substance, and presenting to our view different projections according to the size of the part that remains uncovered. Perhaps they may be parts of some great mass of matter which serves as aliment to the fire of the sun. However, let the sun be what it will, it does not by any means appear habitable.[36] It is a pity; the situation would be advantageous: placed at the centre, its inhabitants would see the planets going round them in regular orbits, whilst to us their motions seem to have perplexing varieties, which are merely the effect of our not observing them from the best place; that is, the centre of their circles. What a sad thing it is: there is but one spot where the study of the celestial bodies would be extremely easy, and at that spot there is nobody to pursue the study. You forget yourself, answered the Marchioness. Were any one placed on the sun, he would neither see the planets nor the fixed stars; would not the light of the sun efface every other object? The inhabitants would doubtless think themselves the only people in existence. [Footnote 36: Some natural philosophers have however thought that the sun might be the cause of heat without being itself hot; and that there was a possibility of its being inhabited. M. Herschel believes its population very abundant. Trans. Philos. 1795. Décade Philosophique.]