state. His chief works were his politics, under the title _Leviathan_,
1651, and his _Elementa Philosophiae_, in three parts (_De Corpore, De
Homine, De Cive_), of which the third, _De Cive_, appeared first (in Latin;
in briefer form and anonymously, 1642, enlarged 1647), the first, _De
Corpore_, in 1655, and the second, _De Homine_, in 1658. These had
been preceded by two books [1] written, like the two last parts of the
_Elements_, in English: _On Human Nature_ and _De Corpore Politico_,
composed 1640, printed without the author's consent in 1650. Besides these
he wrote two treatises _Of Liberty and Necessity_, 1646 and 1654,
and prepared, 1668, a collected edition of his works (in Latin). In
Molesworth's edition, 1839-45, the Latin works occupy five volumes and the
English eleven.[2]

[Footnote 1: Or rather one; the treatise _On Human Nature_ consists of
the first thirteen chapters of the work, _Elements of Law, Natural and
Politic_, and the _De Corpore Politico_ of the remainder.]

[Footnote 2: Cf. on Hobbes, G.C. Robertson (Blackwood's Philosophical
Classics, vol. x.), 1886; Tönnies in the _Vierteljahrsschrift für
wissenschaftliche Philosophie_, Jahrg. 3-5, 1879-81.]

Philosophy is formally defined by Hobbes as knowledge of effects from
causes and causes from effects by means of legitimate rational inference.
This implies the equal validity of the deductive and inductive
methods,--while Bacon had proclaimed the latter the most important
instrument of knowledge,--as well as the exclusion of theology based on
revelation from the domain of science. Philosophy is objectively defined as
the theory of body and motion: _all that exists is body; all that occurs,
motion_. Everything real is corporeal; this holds of points, lines, and
surfaces, which as the limits of body cannot be incorporeal, as well as