unprejudiced empiricism; that nature must be explained from itself, and by
as few principles as possible. Beside inert matter, this requires only two
active forces, on whose interaction all becoming and all life depend. These
are warmth, which expands, and cold, which contracts; the former resides in
the sun and thence proceeds, the latter is situated in the earth. Although
Telesius acknowledges an immaterial, immortal soul, he puts the emphasis
on sensuous experience, without which the understanding is incapable of
attaining certain knowledge. He is a sensationalist both in the theory of
knowledge and in ethics, holding the functions of judgment and thought
deducible from the fundamental power of perception, and considering the
virtues different manifestations of the instinct of self-preservation
(which he ascribes to matter as well).

[Footnote 1: Cf. on Telesius, Florentine, 2 vols., Naples, 1872-74; K.
Heiland, _Erkenntnisslehre und Ethik des Telesius_, Doctor's Dissertation
at Leipsic, 1891. Further, Rixner and Siber, _Leben und Lehrmeinungen
berühmter Physiker am Ende des XVI. und am Anfang des XVII. Jahrhunderts_,
Sulzbach (1819-26), 7 Hefte, 2d ed., 1829. Hefte 2-6 discuss Cardanus,
Telesius, Patritius, Bruno, and Campanella; the first is devoted to
Paracelsus, and the seventh to the older Van Helmont (Joh. Bapt.).]

With the name of Telesius we usually associate that of Franciscus Patritius
(1529-97), professor of the Platonic philosophy in Ferrara and Rome
_(Discussiones Peripateticae,_ 1581; _Nova de Universis Philosophia_,
1591), who, combining Neoplatonic and Telesian principles, holds that the
incorporeal or spiritual light emanates from the divine original light, in
which all reality is seminally contained; the heavenly or ethereal
light from the incorporeal; and the earthly or corporeal, from the
heavenly--while the original light divides into three persons, the One and
All _(Unomnia)_, unity or life, and spirit.