introToPlatonicForms

A general introduction to Plato's Theory of Forms

Starting out with Schofield's 'standard account' of the origins of the theory of forms, found in Malcolm Schofield's chapter in the Oxford Handbook to Plato, 'Plato in his time and place.'

Various additions are my own.

The origins of the theory of Forms

First, we turn to Plato's pupil, Aristotle, for a compact description of the genesis of Plato's theory of Forms. As always, we need to play both a 'believer's game' in which we try to see how Aristotle is right and consistent (that is, we believe that what he writes is right and consistent), but also to subject his claims to critical review for biases, inconsistencies, or other problems.
Aristotle (book 1, chapter 6 of Metaphysics) says that whereas Pythagoreans "assimilate" numbers to the things in the sensible world, Plato is different. Whatever "assimilate" means, we have some details about the origin of Plato's theory of forms here. Namely, Aristotle's words imply that Plato thinks numbers exist separately from the things that we can sense. Aristotle continues, at Metaphysics A6, 987a32-b10, to explain how Plato came to the theory of Forms:

"In his youth, he [Plato] had become familiar first of all with Cratylus and with Heraclitean views to the effect that all perceptible things are always in flux, and there is no knowledge that relates to them. This is a position he later subscribed to in these terms. Socrates, on the other hand, engaged in discussion of ethics, and had nothing to say about the general system of nature. But he was intent on finding out what was universal in this field, and was the first to fix his thinking on definitions. Plato followed him in this, and subscribed to the position that definition relates to something else, and not to the perceptibles--on the kind of grounds indicated: he thought it impossible for there to be a common definition of any of the perceptibles, since they were always changing. Plato, then, called these kinds of realities 'ideas,' and claimed that the perceptibles were something in addition to them, and were all spoken of in terms of them--what he said was that by virtue of participation, the many shared their names with the forms." Metaphysics A6, 987a32-b10

So the idea is that Plato takes over from Socrates a sort of definition, the idea that there must be some one thing that explains why things are what they are, ...
but he combines that with the Heraclitean idea of 'flux,' that nothing we can sense is stably what it is.

Heracleitus of Ephesus (535-475BCE) was a philosopher before Socrates' time who is said to have said, roughly speaking, that all things are constantly changing: the only constant is change. Thus, in the extreme, you are not the same from moment to moment. Everything is like a river, constantly flowing and changing. There is no stable being.
We have nothing but fragments, short and few at that, of Heraclitus' own writing, so we can't really be sure what exactly he the historical Heraclitus meant. We know more about what Plato and Aristotle called "Heracliteanism" and we will explore that in this course in the Theaetetus.

i.e. be aware that the writings of Heraclitus (which are not assigned in this course, but can be read quickly), are different from Heracliteanism in Aristotle and Plato, which we will discuss.

Flux: every perceptible is constantly changing

Not just each particular token of a certain type of thing: that might not be enough to block definitions and knowledge.
Take a type of thing. Each instance of that thing differs from other instances of that thing. So where beauty in a certain painting might be bright colors or certain color combinations, we might find those same colors or color combinations hideous in clothing or hair color. So we cannot say that "bright colors" are beautiful. We say that beauty "changes" from thing to thing: so ... it is in flux? Plato says no: beauty is not in flux: there must be some one thing in virtue of which all beautiful things are beautiful, but no perceptible qualities can be that thing.

The sort of things that Plato and Socrates want to define are: equality, death, justice, beauty, tallness, etc. Not "red" or "tastes like broccoli," or "Sam."

Indeed, sensible things are so constantly shifting that sensible things cannot possibly be used for definitions. So Plato posited Forms as the solution: permanent unchanging things that account for why each instance of a thing is that thing. These Forms are what they are, for all time, and so we can safely refer to them.

think for a moment about some modern scientific definitions: are we chasing forms via perceptibles?

The metre is the length of the path traveled by light in vacuum during a time interval of One 299-million-792-thousand-and-458th of a second (current standard definition according to Wikipedia, the source of all known true and certain infallible facts)
The second is the duration of 9-billion-192-million-631-thousand-and-770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom (found "online somewhere": don't try this citation mode in papers! :-)

Notice how they are trying to identify something that is constant and reliable? Science itself is not so concerned with philosophical questions about what knowledge is, but it can fairly be described as pursuing reliability just as Plato was doing, but doing it through sensibles.

Symposium 211a: "First, it [the form of the Beautiful] is and neither comes to be nor passes away, neither waxes nor wanes"
Phaedo 78c-e says it, the form, is not composite and stays always the same
Republic 485b says it always is and does not vary between coming to be and decaying

The 'standard' story:

Aristotle says Plato learned Heracliteanism from Cratylus (who is portrayed as not too bright in the Cratylus). He did that in his youth.

Later, says Aristotle, he connected it with Socratic search for a definition and came up with the Forms.

In doing so, Plato uses thoughts that are Parmenidean

Parmenides of Elea (fl. early 5th c. BCE) was another Pre-Socratic philosopher. We have the first sustained long argument in philosophy from him.

Parmenides demanded that any object of knowledge be what it is, and be so without qualification. In other words, what is must fully be: it cannot not be in any way.
Parmenides said that it is impossible to think or speak about things that are not: such language is nonsense: it has nothing to refer to.

Parmenides was led to conclude that all being is:

permanent,
unchanging,
unchangeable,
unmoving,
unborn,
undying,
unvarying,
perfectly what it is and fully being.

All other options require us to entertain the idea of not being, which is not and cannot be thought..

So, Plato takes forms to be 'Parmenidean' objects?

Perhaps, but it looks like Parmenides thought all being was one thing with all those traits above.
Plato thinks there are many forms, it seems.
And he thinks that they are different for different things.
But if the "Form of the Good" is simply the whole structure of all the Forms, it may be that the whole edifice is Parmenidean??

By their relationship or interaction with sensible things, Forms explain/account for how sensible things "participate" in the Forms (somehow their relationship to the Forms is explanatory and causal and fundamental).

Plato does not explicitly argue that you cannot know what is in flux (except in the Cratylus, which is held to postdate the Republic, Phaedo, and Symposium, at least according to some: take all Platonic dating with a grain of salt, but not too much)

there are people called "process philosophers" who are very interesting and argue that what we can know are processes. If interested, start with A. N. Whitehead.

A General Introduction to The Theory of Forms itself

There is no one text that full explains a theory of Forms, and what is more, there are differences between the ones that talk about Forms. The Phaedo and the Republic are central. Plato only occasionally provides arguments for his claims about the Forms.
There are many scholars who are hesitant to describe it as a "theory" at all: some flat out refuse to do so. This turns on how one defines "theory." In a loose everyday sense of the term, however, there certainly is a theory of Forms in Plato, or maybe a few different theories of Forms.
In spite of doubts, we will speak as though there is one coherent and consistent theory of Forms in Plato from now on.
The Theory of Forms has both metaphysical and epistemological aspects, as well as moral and linguistic ones.

Metaphysically, Forms exist independent of our minds. They are abstract objects that exist and cause sensible particular objects to be qualified in certain ways (i.e. the Form F causes all sensible particular instances of F to be F).
Metaphysically, Forms are like Parmenides' One. They are unchanging, indivisible, uncreated, undying, divine, intelligible, and uniform.
Plato holds that reality is permeated with morality. In other words, it is not the case that the world exists and morality is something that is imposed upon it or constructed from it or results secondarily from it or is confined to one corner of it or is a quality of it among other qualities, or is otherwise separable or posterior to it. Rather, the world has morality built into it, baked in throughout.

Goodness is not an arbitrary judgement about the world, but rather a fact of the matter, part of the fabric of reality. There is a "Form of the Good" and any F is a good (or maybe a good F) if it fully is F.

Linguistically/epistemologically, forms are the key to explaining what it is that we understand when we understand something.

Knowledge via the Forms and Knowledge of the Forms

Plato's argumentative strategy: he usually tries to obey the 'Dialectical Condition': in other words, Plato tries to build an argument by using at the start only terms that his interlocutors understand and claims with which they agree.

In yet other words, he tries to start from plausible premises that we too can agree with, or at least that are not obviously wrong right off the bat and lead us step by step to his own views.

Just as a thought experiment for a moment, one model of an explanation of X might go as follows:

In explaining what X is, I say that X is:

a) (fill in some claim about X);
b( (fill in some claim about X); and
c) (fill in some claim about X).

Then you ask "what are a, b, c, ..."?
I explain that a is e, f, g; that b is h, i, j; that c is k, l, m; and that d is n, o, p.
Then you ask, "what are e, f, g?" and we get a whole bunch more claims that explain previous claims, etc., etc., etc. ...
... then at some point in this process, I might explain that e is q, r, s; that f is t, u, v; and that g is w, X, y.
WAIT A MINUTE! In that last explanation, I have used X to explain g, which was used to explain a, which was used to explain X! circularity enters the explanations
The explanations go on in this fashion, with you thinking you understand each step. You are deepening your "understanding" as you see more and more connections between the various claims and conclusions.
Each letter in the above is a claim, a statement.

On this model, understanding is rather like using a dictionary, which explains more complicated words in terms of simpler words, but then, to explain the simpler words themselves, it has to use other simple words and some of the more complicated words. It's not simply circular, but it has many many circles in it and forms a web-like structure.

It is circular, if you trace one particular path, but is it "viciously" or "virtuously" circular?
It has been called a "web": each part is interconnected with all others somehow, with no part being foundational.
SO, looking at language, we ask, How can someone outside of the language ever come to understand any of it? that is a bit of a mystery, a "Helen Keller moment" when what used to be meaningless suddenly has meaning. It is obvious that it happens. But how can it happen? HOW do you acquire that first meaning?

Now, switch back from language to explaining reality.

On this model, there is no particular need for Forms to construct such a web explaining reality, but maybe they have a role.

An alternative model of explanation holds that we simply go on forever explaining more and more items that never reuse some previously explained item.

That way of knowing the world would never appeal to forms: it would use things we know to explain things we know. Explanation would involve propositions (knowing "that").

Yet another alternative model says that we explain things using other things, never reusing things, BUT eventually, we get to the bottom of things. We "get to the bottom" when we reach things we can no longer explain at all. These are the foundations of our knowledge.

Perhaps they are just so obvious that no one would question them, or perhaps questioning them would so utterly destroy the possibility of thought and existence that if one accepts thought and existence, one must accept them too.

However you explain it, they are "foundational"

An example or three:

1=1
The principle of non-contradiction (for any P, at most one of P or not-P is true, but not both P and not-P).
I am thinking.

We may be able to doubt those three claims, but doing so will render it very difficult, if not impossible, to be coherent, to think, to communicate, etc., so unless we want to just give up and say we neither think nor communicate, we need those three claims, and probably others.

Plato, however, used the Forms to explain how we know things in the first place: it is not via propositional knowledge. Rather, it appears that Plato is saying that we know them by acquaintance: just as I know a cat by seeing, touching, and feeling it (i.e. by becoming acquainted with it), so I know the Form through some sort of acquaintance with it.

NOTE WELL: this is the "standard account": there is at least one interpretation, that of Gail Fine, which is different from this "standard account": Gail Fine claims that Forms are known not by acquaintance, but by dialectical discussion and by using them in rational thought. I like Gail Fine's explanation. It is found in "Knowledge and Belief in Republic 5-7," an article that is included elsewhere in this course.

Some assumptions that Socrates explores in the Cratylus: What sorts of things have Forms?

Most people say that language is arbitrary: that can be taken in two ways.

1) any given term for some thing(s) could just as well be another term: we could call buildings 'Blunderbusses' and guns 'lovers,' and nothing else would need to change.
2) Language arbitrarily picks out 'things' in the world and gives them names. It could just as well pick out other 'things.' For example, we might decide to call all dogs that have a seed in their fur "flogs" and all dogs that have a cat within 10 feet of them "sprogs." Or we might decide that the animal you know as "Chestnut" the horse is not a brown horse but a horse-ish brown (i.e. that brownness is the basic real thing there and being horsey is just accidental to it).

This option simply allows language to construct whatever however it sees fit, and obviously, it can be done, because I just did it, a little bit.

The first claim seems happy with our ordinary groupings of things: all 'horses' are one sort of thing, and you can call them whatever you like ('hoopoes,' 'bolkibooteryos,' whatever), but they remain a unified group, horses. In other words, natural kinds exist, i.e. things have natures and if you a thing's nature, you cut nature apart in the right way, and language, properly used and constructed, just gives arbitrary names to those naturally occurring kinds of things.
The second claim is more radical: it assumes that our ordinary groupings of things into 'horses,' 'cats,' 'pizzas,' and 'lovers' as well as our ordinary assumption that horses are more basic things than what color their hair is, how big they are, or where they stand in relation to Pluto, are arbitrary, and we could just as well use any other grouping or make anything we want basic, no matter how strange: reality is structured by us, but has no 'natural' structuring into groups of its own, or maybe we just have no way to access that structure and so must construct our own in an arbitrary fashion.
Plato rejects 2, and that is essential for his theory of forms: if 2 is the case, then his theory of Forms won't work, because talk of 'horse itself' will not reliably pick out anything real: it would just be an arbitrary convention (cf. the argument about justice in Republic I).

We might keep parts of Plato's theory and call our theory "Platonic" because of that, but it won't be fully Platonic. Many theories are "Platonic" in that loose way.

Aspects of Platonic Forms: (references are to the Phaedo unless otherwise noted)

1. Forms are the same things as Socrates was searching for (i.e. Piety in the Euthyphro)(65d).
2. Forms are not accessible to the senses (65d, 79a1-5).
3. Forms are accessible to the intellect alone (65d, 79a1-5)
4. Forms are objective (i.e. independent of minds, gods, etc.) (Euthyphro).
5. Forms do not change ever in any way, but sensible things are always changing (78c-d)
6. A Form of F is different from sensible F's in that it just is F, and cannot seem F to one person and not-F to another. (74a-b)
7. Forms are paradigmatic and explanatory: they explain why things are what they are (Euthyphro). The Form of F makes all F things F (the so-called 'One over Many' issue). No color, shape, or other similar thing can do so (100c-e).
8. Forms are divine (80a3, b1)

not sure what this means: in Greek, whatever does not die is divine: in that deatheless sense, Forms are divine.

9. Forms are incorporeal (several passages).
10. Forms have instances in the sensible realm, but instances of a form are not the Form itself, and the Form itself is unqualifiedly whatever it is a Form of, whereas its instances are not unqualifiedly whatever they are instances of (75b).

this aspect involves so-called "self-predication": that is to say, the form Human is itself human. We are going to have to revisit "self-predication": some people think Plato should never have said that forms self-predicate.

11. Forms 'exist': they have a special ontological status that can be fairly described in our everyday language as more real than the things we sense.

A fair question to ask might be "where/when do forms exist?" If we respond "everywhere at all times," we might as well not have answered. And yet, perhaps place/space are sensible things, and so they don't apply to forms? So maybe asking that question is like asking How free is pizza? What color is your love of quilting? or How large freezings is a donut? I.e. asking where and when forms are might be just nonsense questions or category mistakes.

S Marc Cohen in his notes to the Phaedo schematizes an argument for Forms as follows:

We perceive sensible objects to be F.

Whatever F is: it could be a horse, a human, red, large, hot, pizza, etc.
I think that 'x is F' is shorthand for 'x is a member of the set of instances of F' or 'X has F-ness'

But every sensible object is, at best, imperfectly F. That is, it is both F and not F (in some respect - shades of Heraclitus?). It falls short of being perfectly F.

Sometimes saying how a thing falls short is harder than at other times, but still, nothing sensible lasts forever, and so it is not what it is for all time, it changes.

We are aware of this imperfection in the objects of perception.
So we perceive objects to be imperfectly F.

Or maybe it's that we perceive objects to be perfectly whatever each one perfectly is, but none of them are perfectly F, so why are we even talking about perfectly F?

To perceive something as imperfectly F, one must have in mind something that is perfectly F, something that the imperfectly F things fall short of. (E.g., we have an idea of equality that all sticks, stones, etc., only imperfectly exemplify.)
So we have in mind something that is perfectly F.

But none of the sensible things we perceive is perfectly F.

Thus, there is something that is perfectly F (e.g., Equality), that we have in mind in such cases.
Therefore, there is such a thing as the perfectly F, the F itself (e.g., the Equal itself), and it is distinct from any sensible object.