Can two things be different and yet the same at the same time?

For example, a chair (white) does not have one leg and another (black) has all of its legs. As in the question, these two things with different properties are the same.

  • I made an edit which you may roll back or continue editing. Welcome! Apr 20, 2019 at 11:45
  • 1
    For questions like these, I would recommend being careful with the word "different." In many schools of thought, if A and B are different, they are not the same; and if A and B are the same, they are not different. Merely using the word as an adjective on the object could force us to answer "no." However, reading your question, you aren't interested in "A and B are different" you are interested in "A and B have different properties," which is a more nuanced question. Just moving the word "different" around can change the answer, when you get down into questions like these.
    – Cort Ammon
    Apr 20, 2019 at 15:16
  • Thanks Frank :)
    – user38342
    Apr 21, 2019 at 6:46

3 Answers 3


I think these questions boil down to "equivalence" and "identity". When it comes to equivalence, of course there are a lot of examples of such objects, e.g. 1$ banknote and 1$ by change are equivalent in terms of amount of things that we can buy with this money but in terms of usage they are not equivalent, hence not identical with inclusion of this property, as vending machines might accept only coins or banknotes though they are still equivalent.

When it comes to identity, it really depends up to which level of details or respect to which properties we consider objects. For example, two 1$ banknotes are identical for a money spender but for banks they are not - they have unique serial numbers. Even it might go as deep, as atomic structure or precision of sizes, for example, the width of two A4 papers might differ by 0.0001 cm or whatever which manufacturers usually call "acceptable error".

So, the answer is both yes and no, depending which level of details you need.

  • Quite a high level he needs. But it's more about the visible part. Can a fridge be similar to a chair? Theoretically, yes and not because people use it for different purposes but they have a common denominator man. The question is whether something very abstract can be the same as above.
    – user38342
    Apr 21, 2019 at 6:45

It is necessary that they are both different and the same. In order to be different they must be the same in some respect, and to be the same they must be different in some respect.

A comparison of two objects requires they are the same in that both are objects, but different in that they are different objects.

Sameness and difference go hand in hand. When you say 'two things' you define both as being things thus as the same in this respect.

  • What if they're different? For example, a bottle and an animal
    – user38342
    Apr 21, 2019 at 6:38
  • A bottle and an animal are both extended objects and In this sense they are the same. If they are both in your mind then again this is sameness. The categories they occupy overlap. This is why we can compare their differences, that they are the same in some respects. . .
    – user20253
    Apr 21, 2019 at 11:23
  • The last question about the wave function I understand is that if you think anything happens? Can there be anything more in our dimension than we see, for example: computer games one day no one would ever think that such a thing exists. So in our dimension a lot can still happen, right?
    – user38342
    Apr 21, 2019 at 18:24

There exists such possibility in the physics, or more priecly in Quantum mechanics what are known as "Superposition principle". It says you can have one ball which is blue and red at the same time. After all when you observe the ball you will observe just one of these colors (blue or red). We (Quantum physicists) call such phenomenon as collapse of wave function.

  • Thanks for a couple of days, I've been looking for answers
    – user38342
    Apr 20, 2019 at 10:46
  • So two objects next to each other can be the same, even though they have different properties?
    – user38342
    Apr 20, 2019 at 11:20
  • Any references and quotes from those who take a similar position would help support the answer and provide the reader with a place to go for more information. Welcome! Apr 20, 2019 at 11:36

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