# 3 ants walking in the desert

3 ants are walking on a straight path in the desert, one behind the other.

The sun is setting, so the temperature is bearable.

• The 1st one says : There're 2 ants behind me.
• The 2nd one says : There's 1 ant in front of me, and 1 behind me.
• The 3rd one says : There're 2 ants in front of me, and 1 behind me.

How is it possible ?

• Was this really worth posting? Feb 14, 2019 at 10:42
• @stuart stevenson and downvoters: It is worth posting. Don't make me go, oh i did, Latin: Puzzle puzzle puzzle est est. (For bona fides, look at my easily-solved and never-solved ones.) Thank you for contributing, Rémi Henry.
– humn
Feb 16, 2019 at 1:43
• @humn It's not about being easy but being arbitrary, at least for me. Feb 16, 2019 at 18:13
• +1 - Nobody ever said the puzzles here all had to be mind-bending or extremely difficult. Thinking a puzzle is "too easy" is not a reason to down-vote in my opinion. Apr 11, 2019 at 13:24

It could be that

The third ant is lying

Maybe

The second ant is called "me", so the 3rd one is telling the truth

Surely this must be caused by

or something in a similar vein (pun intended), because otherwise it would be impossible

for ants to talk.

Maybe

they're walking westward. As the sun is low, the third ant casts a shadow which it mistakes for another ant due to being delirious from dehydration

it could be the shade of the 3rd ant.

Since this is labeled lateral-thinking, I'll give it a shot. The answer is pretty simple really:

Two of the ants are walking backwards.
While walking backwards, words like "front" and "behind" become ambiguous. When you are walking backwards in some direction, someone ahead of you can be referred to as being in front of you, but they are also literally behind your back so behind you. And vice versa.

Ok, that's interesting, but does it add up?

Actually no. It would have been better if the 3rd ant said there were two ants in front and two behind him. However, I can still make it work. The trick is in the phrase "one behind the other". Taken literally, this actually only resolves the location of two ants, this says nothing about where the third ant is walking. It's like that silly puzzle where two coins add up to exactly 30 cents, but one of them isn't a quarter, what are they? People struggle with it, until you tell them, sure one of the coins isn't a quarter, the OTHER one is! So one behind the other is just referring to two ants.

So, how can we make it work?

Two ants are walking in a straight line, one behind the other. The leader is walking forward, while the ant behind him is walking backwards. The third ant is walking backwards next to the leader of the previous two ants. The third ant is just slightly ahead of the leader. Since he can see both of the ants with his eyes, he can confidently say that two ants are in front of him. However, because he is really walking beside the leader, within a certain margin of error, he cannot say that the leader is behind him, the leader and him are keeping pace with each other and are even, so there is only one ant "behind" him in a sense that that ant is not ahead.

Oh, by the way:

Labeling the ants 1st, 2nd and 3rd doesn't refer to their location either, just the order in which they spoke. So the 1st ant is actually the one behind everybody and is walking backwards. He has two ants behind him. The second ant is the one I called leader, he has one ant behind him, and one ant right in front of his face - in "front" of him. The third ant is the one I described in the previous paragraph.

Done!