In pursuing their physics the Stoics wanted to create a picture of the world which would be completely coherent. Stoic physics can be described in terms of (a) monism, (b) materialism, and (c) dynamism.
As to the relation between the active and the passive principles there was no clear difference. Although the Stoics talked about the active and passive as two separate types of body, it is likely they saw them as merely two aspects of the single material cosmos. Pneuma, from this perspective, is not a special substance intermingled with passive matter, but rather it could be said that the material world has pneumatic qualities. The diversity of the world is explained through the transformations and products of this eternal principle.
"Ekpyrosis" and "Ekpyrotic" redirect here. For the modern cosmological theory, see Ekpyrotic universe.
The process of differentiation is not eternal; it continues only until the time of the restoration of all things. For the cosmos will in turn decay, and the tension which has been relaxed will again be tightened. Things will gradually resolve into elements, and the elements into the primary substance, to be consumed in a general conflagration when once more the world will be absorbed in God. This ekpyrôsis is not so much a catastrophic event, but rather the period of the cosmic cycle when the preponderance of the fiery element once again reaches its maximum. All matter is consumed becoming completely fiery and wholly soul-like. God, at this point, can be regarded as completely existing in itself.
Ekpyrosis itself however, was not a universally accepted theory by all Stoics. Other prominent stoics such as Panaetius, Zeno of Tarsus, Boethus of Sidon, and others either rejected Ekpyrosis or had differing opinions regarding its degree. A strong acceptance of Aristotle's theories of the universe, combined with a more practical lifestyle practiced by the Roman people, caused the later Stoics to focus their main effort on their own social well-being on earth, not on the cosmos. A prime example are the Stoic-influenced writings of the Roman Emperor Marcus Aurelius (121–180). In his Meditations, he chooses to discuss how one should act and live their life, rather than speculate on cosmological theories.
None of the events which occur by Nature are inherently bad; but nor are they intrinsically 'good' even though they have been caused by a good agent. The natural patterning of the world—life, death, sickness, health, etc.—is made up of morally indifferent events which in themselves are neither good nor bad. Such events are not unimportant, but they only have value in as far as they contribute to a life according to Nature. As reasoning creatures, humans have a share in Nature's rationality. The good for a human is to be fully rational, behaving as Nature does to maintain the natural order. This means to know the logic of the good, to understand the rational explanation of the universe, and the nature and possibilities of being human. The only evil for a human is to behave irrationally—to fail to act upon reason—such a person is insane.
To fully characterize the physical world, the Stoics developed a theory of mixing in which they recognised three types of mixture. The first type was a purely mechanical mixture such as mixing barley and wheat grains together: the individual components maintain their own properties, and they can be separated again. The second type was a fusion, whereby a new substance is created leading to the loss of the properties of the individual components, this roughly corresponds to the modern concept of a chemical change. The third type was a commingling, or total blending: there is complete interpenetration of the components down to the infinitesimal, but each component maintains its own properties. In this third type of mixture a new substance is created, but since it still has the qualities of the two original substances, it is possible to extract them again. In the words of Chrysippus: "there is nothing to prevent one drop of wine from mixing with the whole ocean". Ancient critics often regarded this type of mixing as paradoxical since it apparently implied that each constituent substance be the receptacle of each other. However to the Stoics, the pneuma is like a force, a continuous field interpenetrating matter and spreading through all of space.
Every character and property of a particular thing is determined solely by the tension in it of pneuma, and pneuma, though present in all things, varies indefinitely in quantity and intensity.
A certain warmth, akin to the vital heat of organic being, seems to be found in inorganic nature: vapours from the earth, hot springs, sparks from the flint, were claimed as the last remnant of pneuma not yet utterly slackened and cold. They appealed also to the speed and expansion of gaseous bodies, to whirlwinds and inflated balloons.
Just as a relaxation in tension brings about the dissolution of the universe; so in the body, a relaxation of tension, accounts for sleep, decay, and death for the human body. After death the disembodied soul can only maintain its separate existence, even for a limited time, by mounting to that region of the universe which is akin to its nature. It was a moot point whether all souls so survive, as Cleanthes thought, or the souls of the wise and good alone, which was the opinion of Chrysippus; in any case, sooner or later individual souls are merged in the soul of the universe, from which they originated.
The earlier Stoics made right reason the standard of truth. Zeno compared sensation to the outstretched hand, flat and open; bending the fingers was assent; the clenched fist was "simple apprehension," the mental grasp of an object; knowledge was the clenched fist tightly held in the other hand. But this criterion was open to the persistent attacks of Epicureans and Academics, who made clear (1) that reason is dependent upon, if not derived from, sense, and (2) that the utterances of reason lack consistency. Chrysippus, therefore, did much to develop Stoic logic, and more clearly defined and safeguarded his predecessors' position.
a. ^ Some historians prefer to describe Stoic doctrine as "corporealism" rather than "materialism". One objection to the materialism label relates to a narrow 17th/18th-century conception of materialism whereby things must be "explained by the movements and combination of passive matter" (Gourinat 2009, p. 48). Since Stoicism is vitalistic it is "not materialism in the strict sense" (Gourinat 2009, p. 68). A second objection refers to a Stoic distinction between mere bodies (which extend in three dimensions and offer resistance), and material bodies which are "constituted by the presence with one another of both [active and passive] principles, and by the effects of one principle on the other". The active and passive principles are bodies but not material bodies under this definition (Cooper 2009, p. 100).
b. ^ The concept of pneuma (as a "vital breath") was prominent in the Hellenistic medical schools. Its precise relationship to the "creative fire" (pyr technikon) of the early Stoics is unclear. Some ancient sources state that pneuma was a combination of elemental fire and air (these two elements being "active"). But in Stoic writings pneuma behaves much like the active principle, and it seems they adopted pneuma as a straight swap for the creative fire.
Long 1996, p. 45 - Long, A. A. (1996), "Heraclitus and Stoicism", Stoic Studies, University of California Press, ISBN 0520229746
Hicks 1911, p. 943 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Algra 2003, p. 167 - Algra, Keimpe (2003), "Stoic Theology", in Inwood, Brad (ed.), The Cambridge Companion to the Stoics, Cambridge University Press, ISBN 0521779855
White 2003, p. 129 - White, Michael J. (2003), "Stoic Natural Philosophy (Physics and Cosmology)", in Inwood, Brad (ed.), The Cambridge Companion to the Stoics, Cambridge University Press, ISBN 0521779855
Sambursky 1959, p. 5 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
Sambursky 1959, p. 114 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
Sambursky 1959, p. 41 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
Long 1996, p. 45 - Long, A. A. (1996), "Heraclitus and Stoicism", Stoic Studies, University of California Press, ISBN 0520229746
Algra 2003, p. 167 - Algra, Keimpe (2003), "Stoic Theology", in Inwood, Brad (ed.), The Cambridge Companion to the Stoics, Cambridge University Press, ISBN 0521779855
Long 1996, p. 46 - Long, A. A. (1996), "Heraclitus and Stoicism", Stoic Studies, University of California Press, ISBN 0520229746
Sellars 2006, pp. 81–82 - Sellars, John (2006), Ancient Philosophies: Stoicism, Acumen, ISBN 9781844650538
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Plato, Sophist, 247D
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Sambursky 1959, p. 31 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
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Sellars 2006, p. 90 - Sellars, John (2006), Ancient Philosophies: Stoicism, Acumen, ISBN 9781844650538
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Hicks 1911, p. 944 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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Hicks 1911, p. 944 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 944 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Heraclitus, DK B60
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Hicks 1911, p. 944 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 944 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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The extent to which Stoics discussed and disagreed regarding Ekpyrosis is largely attributed to works of Hippolytus of Rome, found in the Stoicorum Veterum Fragmenta. /wiki/Hippolytus_of_Rome
Mannsfeld, Jaap (September 1983). "Resurrection Added: The Interpretatio Christiana of a Stoic Doctrine". Vigiliae Christianae. 37 (3): 218–233. doi:10.1163/157007283X00089. /wiki/Doi_(identifier)
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Sambursky 1959, p. 12 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
Sambursky 1959, p. 12 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
Sambursky 1959, p. 13 - Sambursky, Samuel (1959), Physics of the Stoics, Routledge
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Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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Sellars 2006, p. 105 - Sellars, John (2006), Ancient Philosophies: Stoicism, Acumen, ISBN 9781844650538
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
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Algra 2003, p. 167 - Algra, Keimpe (2003), "Stoic Theology", in Inwood, Brad (ed.), The Cambridge Companion to the Stoics, Cambridge University Press, ISBN 0521779855
Sellars 2006, p. 105 - Sellars, John (2006), Ancient Philosophies: Stoicism, Acumen, ISBN 9781844650538
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Seneca, Epistles, liii. 11–12
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 945 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Diogenes Laërtius, vii. 54
Cicero, Academica, ii. 4
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
Sellars 2006, p. 56 - Sellars, John (2006), Ancient Philosophies: Stoicism, Acumen, ISBN 9781844650538
Hicks 1911, p. 946 - Hicks, Robert Drew (1911). "Stoics" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 942–951. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Stoics
White 2003, pp. 134–136 - White, Michael J. (2003), "Stoic Natural Philosophy (Physics and Cosmology)", in Inwood, Brad (ed.), The Cambridge Companion to the Stoics, Cambridge University Press, ISBN 0521779855