hy_, Sec.3589. Eng. trans., London, 1847.

[8-1] Von Feuchtersleben, _The Principles of Medical Psychology_, p. 130
(Eng. trans., London, 1847).

[9-1] "The fundamental property of organic structure is to seek what is
beneficial, and to shun what is hurtful to it." Dr. Henry Maudsley,
_Body and Mind_, p. 22.

"The most essential nature of a sentient being is to move _to_ pleasure
and _from_ pain." A. Bain, _On the Study of Character_, p. 292 (London,
1861).

"States of Pleasure are connected with an increase, states of Pain with
an abatement of some or all of the vital functions." A. Bain, _Mind and
Body_, p. 59.

"Affectus est confusa idea, qua Mens majorem, vel minorem sui corporis,
vel alicujus ejus partis, existendi vim affirmat." Spinoza, _Ethices_,
Lib. III. _ad finem_.

[11-1] The extension of the mechanical laws of motion to organic motion
was, I believe, first carried out by Comte. His biological form of the
first law is as follows: "Tout etat, statique ou dynamique, tend a
persister spontanement, sans aucune alteration, en resistant aux
perturbations exterieures." _Systeme de Politique Positive_, Tome iv. p.
178. The metaphysical ground of this law has, I think, been very well
shown by Schopenhauer to be in the Kantian principle that time is not a
force, nor a quality of matter, but a condition of perception, and hence
it can exert no physical influence. See Schopenhauer, _Parerga und
Paralipomena_, Bd. II, s. 37.

[13-1] "Aller Genuss, seiner Natur nach, ist negativ, d. h., in
Befreiung von einer Noth oder Pein besteht." _Parerga und Paralipomena._
Bd. II, s. 482.

[14-1] "No impression whatever is pleasant beyond the instant of its
realization; since, at that very instant, commences the change of
susceptibility, which suggests the desire for a change of impression or
for a renewal of that impression which is fading away." Dr. J. P.
Catlow, _The Principles of Aesthetic Medicine_, p. 155 (London, 1867).

"Dum re, quem appetamus fruimur, corpus ex ea fruitione novam acquirat
constitutionem, a qua aliter determinatur, et aliae rerum imagines in eo
excitantur," etc. Spinoza, _Ethices_, Pars III, Prop. lix.

[18-1] "Feeling and thought are much more real than anything else; they
are the only things which we directly know to be real."--John Stuart
Mill.--_Theism_, p. 202. How very remote external objects are from what
we take them to be, is constantly shown in physiological studies. As
Helmholtz remark