Spinoza's Ethics: II.P16

Idea cujuscunque modi quo corpus humanum a corporibus externis afficitur, involvere debet naturam corporis humani et simul naturam corporis externi.

Translated as,

An idea whose mode in which the human body is affected by external bodies ought to involve the nature of the human body and at the same time the nature of the external body.

DEMONSTRATIO: Omnes enim modi quibus corpus aliquod afficitur ex natura corporis affecti et simul ex natura corporis afficientis sequuntur (per axioma 1 post corollarium lemmatis 3) : quare eorum idea (per axioma 4 partis I) utriusque corporis naturam necessario involvet adeoque idea cujuscunque modi quo corpus humanum a corpore externo afficitur, corporis humani et corporis externi naturam involvit. Q.E.D.

Translated as,

For all modes by which some body is affect follow from the nature of the affected body and at the same time from the nature of the affecting body (by A1 after L3C): wherefore the idea of those (by IA4) involves by necessity the nature of each body to the extent that the idea of whose mode in which the human body is affected by an external body involves the nature of the human body and the of the external body.

COROLLARIUM I: Hinc sequitur primo mentem humanam plurimorum corporum naturam una cum sui corporis natura percipere.

Translated as,

From here it follows first that the human mind perceives the nature of more bodies with the nature of its own body.

COROLLARIUM II: Sequitur secundo quod ideæ quas corporum externorum habemus, magis nostri corporis constitutionem quam corporum externorum naturam indicant; quod in appendice partis primæ multis exemplis explicui.

Translated as,

Next it follows that the ideas which we have of external bodies indicate more the constitution of our own body than the nature of the external bodies; which I have explained in the appendix of part one by means of multiple examples.

Spinoza's Purpose in Writing The Ethics

In another treatise On the Emendation of the Intellect, Spinoza writes of his desire to discover a way to achieve "continuous, supreme and unending joy." It does look like this is related to The Ethics as the work begins with a view of infinite reality and ends with human freedom, but is that where Spinoza takes himself and us along with him?

Augustine comments in The Confessions that "all humans want to be happy" in a propositional sounding phrase that would please Spinoza. Spinoza spends significant chapters of the emotions of sadness, joy and desire and encourages a pleasant life, but the longer I live with this work, the less it appears to be focused on being connected with the highest happiness. If not, what is it?

First of all, Spinoza spends significant time discussing God's expressiveness. God expresses through modes, of which we are each one. This expressiveness is not teleological, that is, God does not express for achievement of some goal. Rather the expressiveness is the manifestation of potential power which necessarily optimizes because God necessarily optimizes. 

As a modal expression of God's power, it would appear that each of us is expressive and that our expressiveness is a function of power. For that reason, health, education and social resources allow fuller expression of our modality - a virtual self becoming actual through interactions. 

It would appear that Spinoza's attributal division of extending and thinking means that our mind registers joy as the freedom to fully express ourselves, even when our mind is clouded by delusions of imagination to see ourselves as powerful. Certainly such a state seems unlikely to be what Spinoza is discussion. Instead reality and perfection are the same thing so as we move to reality, we also move to perfection and greater sustainable joy. 

Does that mean that great scientists have greater joy? I think Spinoza might reply that it depends on the fullest expression of self, which might entail notions of greater health or wealth. Instead, as I continue to explore this work, I would hazard that the ability to be fully present, without the delusions of imagination, by good health, reason and resources, represents the point of optimal modal expression of some virtual becoming actual and that optimal modal expression is the purpose.

Spinoza's Ethics: II.P15

Idea quæ esse formale humanæ mentis constituit non est simplex sed ex plurimis ideis composita.

Translated as,

The idea which constitutes the formal essence of the human mind is not simple but composed of more ideas.

DEMONSTRATIO: Idea quæ esse formale humanæ mentis constituit, est idea corporis (per propositionem 13 hujus) quod (per postulatum 1) ex plurimis valde compositis individuis componitur. At cujuscunque individui corpus componentis datur necessario (per corollarium propositionis 8 hujus) in Deo idea; ergo (per propositionem 7 hujus) idea corporis humani ex plurimis hisce partium componentium ideis est composita. Q.E.D.

Translated as,

The idea which constitutes the formal essence of the human mind is the idea of the body (by IIP13) which (by postulate 1) is composed of individual parts composed of even more individual parts. But the body of whatever individual exists by necessity by components (by IIP8C) in God by idea; therefore (by IIP7) the idea of the human body is composed of more ideas of component parts.

Spinoza's Ethics: II.P14

Mens humana apta est ad plurima percipiendum et eo aptior quo ejus corpus pluribus modis disponi potest.

Translated as,

The human mind is suitable for perceiving more things and where it is more suitable there its body is able to be arranged in more ways.

DEMONSTRATIO: Corpus enim humanum (per postulata 3 et 6) plurimis modis a corporibus externis afficitur disponiturque ad corpora externa plurimis modis afficiendum. At omnia quæ in corpore humano contingunt (per propositionem 12 hujus) mens humana percipere debet; est ergo mens humana apta ad plurima percipiendum et eo aptior etc. Q.E.D.

Translated as,

For the human body (by postulates 3 and 6) is affected in more ways by external bodies and is arrranged for affecting external bodies in more ways. But everything which touches on the human body (by IIP12) the human mind ought to perceive; thus the human mind is suitable for perceiving more things and where it is more suitable etc.

Spinoza's Ethics: Postulates

These postulates set up a kind of corporeal physics which is all-important if the object of the mind is the body. Most of the postulates are self-evident. However, V is different and appears to set up a structure for memory functions of encoding an experience.  

I. Corpus humanum componitur ex plurimis (diversæ naturæ) individuis quorum unumquodque valde compositum est.

Translated as,

The human body is composed of more individuals (of a diverse nature) of which each and every one is richly composed of. 

II. Individuorum ex quibus corpus humanum componitur quædam fluida, quædam mollia et quædam denique dura sunt.

Translated as,

Of the individuals of which the human body is composed, certain ones are fluid, certain ones are soft and finally certain ones are hard.

III. Individua corpus humanum componentia et consequenter ipsum humanum corpus a corporibus externis plurimis modis afficitur.

Translated as,

The human body is individual components and consequently the human body itself is affected by external bodies in more ways.

IV. Corpus humanum indiget ut conservetur plurimis aliis corporibus a quibus continuo quasi regeneratur.

Translated as,

The human body needs so that it must conserve from more other bodies by which it is as if continuously regenerated.

V. Cum corporis humani pars fluida a corpore externo determinatur ut in aliam mollem sæpe impingat, ejus planum mutat et veluti quædam corporis externi impellentis vestigia eidem imprimit.

Translated as,

Since the fluid part of the human body is determined by an external body so that it touches often on another soft [part] whose surface changes and as such leaves a certain vestige of the force of the external body on the same.

VI. Corpus humanum potest corpora externa plurimis modis movere plurimisque modis disponere.

Translated as,

The human body is able to move outside bodies by more ways and to displace them in more ways.