Core Aspects of (Greek-Roman) Ancient Philosophy

by Dr. Jan Garrett

PHIL 302 -- Fall 2007

Revised August 10, 2007


To discover what is real and essential in being and life, primarily by use of reflective reason. (See assumptions.)


How should we live our lives? (What kind of life is preeminently worth living?)

Given that inquiry is an activity worth pursuing, what are the basic realities/causes of things?

Given that untested opinion on these matters cannot count as an answer, what can we know? (Are there any questions that are inherently unanswerable?)

From (3), how can we know? In what ways can knowledge-claims be justified?

Given multiple answers to these questions, what is the best way to choose among them?


Careful observation using the naked senses; sometimes the reports of others (e.g., travelers).

What all or most people say; what the reputedly wise say.


Cause (material, formal, final, efficient)
Essence; substance and accident
Capacity, Action, Moral Character, Virtue and Vice, Happiness
Ignorance, opinion, knowledge.
Mind, soul, and body.
Rational and nonrational activity; types of rational activity: knowing vs. inquiring; deliberating vs. acting; being vs. becoming; etc.
Truth as agreement between mind (or language) and reality. (This is usually an assumption, only rarely stated, say, in Aristotle.)


(Note: A few, like the Skeptics, call into question the assumptions, among those below, that lead to optimism about the human capacity for knowledge.)

  • Folk theories such as:
         1) The universe is an intelligible place.
         2) Things have essences, causes that explain why they behave as they do
         3) Things are classified naturally into kinds (by their common essences)
         4) There is an all-inclusive category.
  • Among the causes, a small number (or a small number of kinds) are most basic.
  • The popular religion contains misleading beliefs, but, generally it plays an important social role; it should be refined for philosophical purposes rather than rejected. (Prior to the Stoics philosophers do not engage in systematic "scientific" discourse about the gods.)
  • Very few intellectual questions are ruled out in advance. But see the other assumptions.
  • Geometry reveals the best way to organize knowledge, from ultimate principles to conclusions by way of intermediate steps and middle terms (although moral reasoning may not live up to the model).
  • Certain folk theories are accepted; and certain metaphorical logics are assumed to reveal truth; these vary from philosopher to philosopher or school to school.
  • Consistency is a mark of a true theory
  • Well-brought up adults (and there are many in our society) already "know" in a rough sense what the basic truths are, at least in ethics, but we must have a method (e.g., dialectic) to extract this from what they say.
  • Philosophical solutions can be found without getting your hands dirty and without relying too much for data on those who must get their hands dirty. (There are very few if any experiments on the part of ancient philosophers.)


  • What might have been learned by experimentation, by "torturing nature," is not learned.
  • Theories of truth other than the correspondence theory are not really considered.
  • In spite of occasional tensions between philosophy, on the one side, and the masses or tyrants, on the other, ancient philosophers played a mildly reformist role in practice; if active in civic life, they preferred to be advisors rather than leaders of major reforms.


    Determined by the assumptions.