Who knows √-1?

The traditional Passover song "Echad - mi yodeya" implies a possible presupposition that there is a Jewish significance to be found for each number.

What significant Judaism facts are there about the square root of -1?

This question is Purim Torah and is not intended to be taken completely seriously. See the Purim Torah policy.


5 Answers 5


√-1 is an extremely important number in Judaism. Of course, everybody knows √-1 is equal to i. We also know that i is equivalent to Hashem, as the posuk says (actually many p'sukim say so)

אני ה'‏

I am Hashem.

  • 2
    And this is where my habit of not capitalizing "i"s is useful. :)
    – Scimonster
    Commented Mar 10, 2016 at 20:55
  • 4
    @Scimonster Here it's only capitalized because it's the beginning of the sentence.
    – Daniel
    Commented Mar 10, 2016 at 20:55
  • Well done... I was trying to figure out some way to deal with "root" and "minus," but this takes the cake... Commented Mar 10, 2016 at 20:59
  • 3
    Doesn't this imply that √-1 = 1 ?
    – Double AA
    Commented Mar 16, 2016 at 13:43
  • 3
    @DoubleAA I did think of that difficulty. I don't have a definite answer. My best understanding is that the transitive property doesn't apply to God.
    – Daniel
    Commented Mar 16, 2016 at 14:19

Who knows √-1?



√-1 is very important in Judaism because it teaches that what appears to be "imaginary" actually exists and has a major influence on the universe. The minim who pretend that Olam haruach is "imaginary" because it is not immediately visible are defeated because they are confronted with this fact. Another point is that the √-1 shows that the universe cannot exist without the "imaginary" component even though we try to ignore it.

  • 3
    This is some profound Purim Torah. I'm impressed.
    – Mike
    Commented Mar 11, 2016 at 2:56

As we all know, √-1 is equal to j. This is the J strand of the Bible, according to the Documentary Hypothesis. It is particularly important that we remember that j = √-1, because we must always keep in mind that the Documentary Hypothesis is imaginary.

  • The last line is the kicker :)
    – user9907
    Commented Mar 21, 2016 at 1:32

√-1 is the imaginary unit, used as the basis for all imaginary numbers, which are used to count imaginary things. Generally speaking, imaginary things are a theoretical concept, invented by mathematicians so that they can plead that the imaginary numbers that they also invented have a practical application. However, there is one real-world killer application of imaginary numbers - counting sheep when one is plagued with insomnia. As the sheep in question are imaginary (unless one is a shepherd, I guess), they require imaginary numbers for the counting, so the only way the cure is effective is if √-1 is employed.

Unfortunately for Achashveirosh but fortunately1 for us, when he suffered from insomnia, imaginary numbers were yet to be invented for centuries, so the sheep-counting therapy was unavailable, and he had to resort to reading logs, which, again fortunately1, again had been invented, if rudimentarily.

1. By which I mean "thanks to God's intervention in the history of mathematics." There; I said it.


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