Trying to answer the question: "What are the things?"

I noticed that different things have different (physical) forms and that equal things have equal forms. But what if it was a wrong reasoning ?

I wondered: "What if all things have different forms and we just don't notice/see it (are just incapable of seeing it)? Then think how can something be "equal" to something else?

If something is "equal" to something else, isn't it only equal to itself? Because if it wasn't it wouldn't be "totally equal" (by "equal" I mean ALL the properties are the same), it wouldn't exist in the same place, it wouldn't be surrounded by the same air/thing...

Can something really be equal to something besides itself?

After that thought, I tried to define all the things: "Things are there form" (Since different things have different physical forms) I tried to search by this "thought experiment?" but I could only find Plato's theory of forms, which isn't the idea proposed.

By "physical form" i meant: the physical structure of an object (I do not mean the outline of an object). To make it more clear, imagine two almost perfect metal spheres side by side, using the concept provided I would say that "They are not the same/equal", they are in different locations, they are formed by different entities... (physical properties)

  • 2
    Leibniz' identity-of-indiscernibles/indiscernibility-of-identicals, and the scholastic (and arcane) notion of haecceities, pertain to this question. Commented Sep 13, 2023 at 22:45
  • What is the "form of a thing"? Do you mean the matter-form conception as in Plato and Aristotle? Whether something be equal to something else depends on the meaning of "equal". A circle and a square can be equal by area, two different circles can be equal by shape, etc. In fact, two different things can be qualitatively identical in all respects and only distinct numerically, by location in space or by so-called haecceity (indexical "thisness"), for example, see SEP, Identity.
    – Conifold
    Commented Sep 13, 2023 at 22:53
  • @Conifold By "form of a thing" I mean the external boundary that the physical objects have. As for your examples I would say that since a number doesn't have a form and only one of itself, it can be totally equal to itself, and since the quantity/amount of an area can be expressed by a number the area can be the same (but the surface is not, given that they can have form) Commented Sep 13, 2023 at 23:09
  • Numbers do not have any special status, and neither does "form" (i.e. shape, as you use the word, "form" has a different meaning in philosophy). Shapes are "totally equal to themselves" just like numbers, and so are colors, structures, or any other abstractions. Circles of different size have the same shape, you can define many other equivalence relations, as they are called, by which things can be equal too. By the way, "numerical" in "numerical identity" has nothing to do with numbers, it is just a term opposed to "qualitative".
    – Conifold
    Commented Sep 13, 2023 at 23:57
  • 1
    Maybe useful André J. Abath, Knowing What Things Are: An Inquiry-Based Approach (Springer, 2022) Commented Sep 14, 2023 at 6:02

1 Answer 1


You talk about the Law of Identity, which is definitional in classical logic, and mathematics. But in the world, consider Heraclitus' point that we can never step in the same river twice, or the Ship of Theseus. Buddhist philosophy poses a radical ontological challenge to the Law of Identity applying to the world, and to the idea of anything being stable and unchanging, with the core Buddhist concepts of Anatta (no self that continues unchanged) and Sunyata (dependent origination, everything is involved in how it is with how others things are and it's all in flux).

You settle on form, but what about formless things, like say abstract ideas?

You might like to read about how Wittgenstein's stance encompassed both abstract logical statement and statements of facts in his ontology: The world is all that is the case (Philosophy Now magazine article).

  • 1
    I don't know to what that thought that I had align to. The identity of indiscernibles, the haecceities and the law of Identity all seems to me to line up. Also loved to read that article, but was very confused with the definition of "facts". Thank you for answering Commented Sep 14, 2023 at 16:14

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .