Can it be true that 1 + 1 = 1?


Can you have 1+1 = 1? Generally it seems not. But God the Father is one person and God the Son is one person. What happens when you have God the Father and God the Son, i.e., 1+1? You get 1 because Jesus says I and the Father are One. How can it be that one person plus one person is one?


I’m no expert, but God cannot be measured by our meager mathematics. Besides that, shouldn’t it be 1+1+1=1? Referring to the Trinity.


John 10:30 is not speaking of “persons” being “1”. It is speaking of unity of purpose of both the Person/Being of the Father and Person/Being of the Son. See John 5:17, and the context of Jesus working in John 10 in harmony with the Father.

1+1 does not equal 1 (except in the concept of unity of purpose, as at-one-ment, such as husband and wife, team, family, etc 4 gospels, the OT and NT).
1 +1 may equal 2, and/or it may equal Duo (2 working together harmoniously).


The only problem with that is that unity of purpose would not imply the divinity of Jesus and this passage is often invoked to support the divinity of Jesus. You can have the same purpose as the Divine Being without being divine yourself.


Except that the remaining context of John 10, including verse 30, demonstrates the Deity of Jesus. What it doesn’t demonstrate, is that the Person/Being of the Son, is the same as the Person/Being of the Father.


A perfectly valid expression in Boolean mathematics.

I was reading a book about the Arian crisis by Rod Bennet recently. One thing that I found interesting was a comment he made relating the Trinity to a black hole.

With black holes, we cannot really know what it’s like inside one. It bends our reality too much for a true understanding. But by looking at what’s around it and through other observations, we can know what a black hole is not andas we learn more about what it’s not, we’re left with what it is even if it makes no sense to our minds.

So with the Trinity we can study Scripture and know what God is not. Arianism, Sabellianism, Modalism, ect. can all,be shown to be what God is not and that leaves us with what He is, the Trinity, even if it doesn’t make sense to our minds.


Persons and Beings are not the same unit or necessarily convertible with each other.

1 person + 1 person + 1 person is 3 persons. It’s not 3 beings.

Christians do not claim 1 being + 1 being + 1 being = 1 being. That is nonsense.


In logical notation, where we’re talking about true & false, and operations of ‘or’ and ‘and’, sure. That’s a valid equation.


Because there are not three independent gods or even persons. The number is order rather than essence. The Catechism 252 states that the Church gave a new and unprecedented meaning to the terms “substance”, “person” or “hypostasis”, and “relation” to express the mystery of the Holy Trinity:

  • The Church uses … the term “relation” to designate the fact that their distinction lies in the relationship of each to the others.


Two moles of hydrogen plus one mole of oxygen makes one mole of water.

I know this probably doesn’t apply. But I wanted to bring it up to possibly spur thought. :slight_smile:


(God the Father) X (God the Son) X (God the Holy Spirit) = 1 God :rofl:


If one of the ones identifies as a zero.


Love it! :smile:

I was thinking along similar lines:

1 half note + 1 half note = 1 whole note

I could stretch it out further and say:

1 quarter note + 1 quarter note + 1 quarter note + 1 quarter note = 1 whole note.

In food prep, I could say:

1 apple + 1 pineapple + 1 banana = 1 fruit salad

For the lateral thinker, the possibilities are endless! (and just way too much fun) :crazy_face:


Mathematical addition is meant for the natural/physical world, for human purposes. God is above that. The human mind can never fully understand God so your equation is an oversimplified representation.


With GOD all things are possible.


But Jesus said: I and the Father are One? Does that amount to saying that the two are one?


Same being in terms of divinity, different persons.


It says they are one, but not in the mathematical sense, the chemistry sense, or the boolean sense.

Jesus is talking about theology, about God.

In binary notation 1+1 = 10 . We always have to define the context, That’s what is at issue here.

it’s easy to ask a challenging question – can 1+1=1 – but the answer can require a lot of explanation. When it comes to the Bible, like this question is, the topic should be approached with faith (first of all) and then with prayer and Bible study.

The original question is oversimplified into a mathematical formulation. That step is unwarranted in a theological discussion. Catholics take a “canonical” approach to Bible study – any answer must be held up against what the Bible says overall, and according to Tradition and the Magisterium of the Church.

The books of Job and Ecclesiates pose simple questions and answers, which are proven to be inadequate.


In set theory, the union of three sets that each contain only one would result in a single set that itself only contains one. In other words:

{1} ∪ {1} ∪ {1} = {1}

Alternatively, you can replace the numbers with “Father”, “Son”, and “Holy Spirit” and get:

{Father} ∪ {Son} ∪ {Holy Spirit} = {Father, Son, Holy Spirit}

That’s probably the most relevant mathematical representation of the Trinity, since the Trinity is, in fact, a perfect union. This, of course, has one set containing three distinct values. That’s similar to how the Trinity is one being containing three distinct persons.

Basically, by selecting standard arithmetic addition, you assume no union, which is a faulty representation of the Trinity. As a result, set theory, which does have a union, is perhaps more apt for this kind of analysis than the arithmetic we learn as three years olds.


Even from a linguistic perspective, this can still be possible. When speaking of substantive nouns, the number of the noun always remains the same, the substance of the noun simply increases.

For example, if you have one school of fish and add to it another school of fish, you still end up with a single school of fish, it is just a larger school.

This unity is actually why the description of the three persons of the Trinity changes slightly when speaking of them in the unity of the Trinity and as the distinct persons.

Generally, when speaking of persons, it is “The Father, and the Son, and the Holy Spirit.” (Sign of the Cross) But when speaking as the Trinity as a whole, it is generally “Father, Son and Holy Spirit” (Collect for Trinity Sunday). The distinction or unity is observed in the description of the persons.

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