In the kingdom of Calendria, the natives all lie during months with English names beginning with vowels and tell the truth in the other months. One native makes the following two statements:

• I lied last month.
• I will lie again six months from now.

In what month were the two statements made?

April, August and October are the only months in which he will lie.

The statement could be made in August.  He would tell the truth in both July (last month) and February (six months from now), but being a liar at the time the statements are consistent.

The statements could not be made in Apr or Oct because they are 6 months apart.  He falsely say he would tell the truth in six months.

For truth telling months we would need the preceding month and the month six away to be lying months.  But no two of the vowel months are 7 apart.

So the only possibility is the statements were made in August.

Posted by Jer on 2011-02-10 18:04:29