Correspondence, by Benedict de Spinoza, [1883], at sacred-texts.com
[A continuation of the arguments in favour of ghosts, which may be summarized as follows:I say a thing is done by chance, when it has not been the subject of will on the part of the doer; not when it might never have happened.Necessity and freedom, not necessity and chance, are contraries.If we do not in some sense attribute human qualities to God, what meaning can we attach to the term?You ask for absolute proof of the existence of spirits; such proof is not obtainable for many things, which are yet firmly believed.Some things are more beautiful intrinsically than others.As God is a spirit, spirits resemble Him more than embodied creatures do.A ghost cannot be conceived as clearly as a triangle: can you say that your own idea of God is as clear as your idea of a triangle?As a circle exists without a sphere, so a sphere exists without a circle.We call things higher or lower in proportion to their distance from the earth.All the Stoics, Pythagoreans, and Platonists, Empedocles, Maximus Tyrius, Apuleius, and others, bear witness to ghosts; and no modern denies them.
[paragraph continues] It is presumption to sneer at such a body of testimony. Cæsar did not ridicule ghosts, but omens, and if he had listened to Spurina he would not have been murdered.]