How many holes does the t-shirt have (a.k.a. Why one should not trust brain teasers on the Internet)

Figure 1: Source [1]
The above is a brain teaser posted by a website [1]. I am pretty sure that you have seen this question before and taken by heart the answer that they give; which is either 4 or 8. I have copy pasted the explanation from the site below;

There are two right answers of this question.

1. The number of holes in this shirt is four as we can see the background through the holes. It means the holes exist on both sides of the T-shirt.

2. If you count the holes of body, sleeves and neck, then there are eight holes in the T-shirt.

However, the above is not correct. The correct answer for this was given by Matt Montalvo on Facebook [2]. I have copy pasted his answer in verbatim;

The correct answer is at least 7 or more. Impossible to confirm without seeing 100% of the shirt from a 360 perspective.

As a normal T-shirt, we know it has 4 holes, 2 for the arms, one for the head, and one at the waist. That brings the total to 4.

We can also confirm there is two holes in the front, which means the total is at least 6 now.

The back is not in view, however, you can see the green background, so there is at least 1 hole in the back, however there can be any number of holes. There can be holes behind the parts of the shirt that appear untouched from the front, such as near the bottom of the shirt, or anywhere we cannot see through, however it is nothing you can confirm since you cannot see it, but also by the same logic, you cannot expel that same notion to hypothesize a solid number for an answer, so the only “correct” answer must be equal to or greater than x. If we are at 6, and there is a possibility of the back of the shirt having 1 giant hole, or 2 holes equal to or near the size in relation to the perspective of the holes in the front of the shirt, that would mean we can easily theorize with evidence, 7 or 8 holes. However, to say 8 is to denote the hypothesis of the holes in the back could be one giant hole, meaning it is less than 8, and it is 7 or more. You cannot reject the hypothesis that there is 7 holes or more, but you can reject that there is 8, because there is a possibility that the hypothesis supporting 8 holes is wrong.

The correct answer is there is equal to or greater than 7 holes in the shirt. 8 is applicable to that, yes, but 8 in itself is not the correct answer, because there could be 7, and there could be as many as 20.

The article/link is incorrect. There could be 8, but there could be 7 as well. Saying that there is at least 7 or greater is not the same as saying 8. 8 is 7 or greater, but 7 or greater is not 8. Its logic. They are not synonymous.

Here’s an instance.

Hypothesis: Does the trial meet the criteria from the constraint “7 or greater”, trial being 8?

8 IS 7 or more, because 8 is one more than 7, so yes.

Now flip that.

Hypothesis: Does the trial meet the criteria from the constraint “8”, trial being 7 or greater?

If that number is 8, yes, it is correct, however, 7 or greater can be any number equal to or greater than 7, so although it in one instance is correct, by every other value, it is literally infinitely incorrect, unless that number is 8. Thus, we can reject the hypothesis that 8 is 7 or greater, yet acknowledge that 7 or greater can in fact be equal to 8. Using this logic, anyone who says 8, is incorrect. Think of it as the Price is Right, you just went over, and are now rejecting that 7 is a possibility, but also rejecting any number other than 8. 8 is only one of an infinite number of answers, and even if you do not want to count the possibility of holes being in the back that cannot be seen, that would mean you believe in a finite number of solutions; 2 solutions: 7 or 8 holes, which is still not 8, and 8 is still an incorrect answer by the same logic.

Yes, I am fun at parties, and I hate math, I just like thinking outside the box, and being precise in my answer.

When some people disagreed with him, he literally took a shirt, cut it and proved his point.

Figure 2: Source

Now that, ladies and gentlemen,  is what I call commitment to logic.



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