Bouzouki Asia Minor and the subsequent exchange of populations between Greece and Turkey when the ethnic Greeks fled to Greece. The early bouzoukia were mostly three-string ("trichordo"), with three courses (six strings in three pairs) and were tuned in different ways, as to the scale one wanted to play. At the end of the 1950s, four-course (tetrachordo) bouzoukia started to gain popularity. The four-course bouzouki was made popular by Manolis Chiotis, who also used a tuning akin to standard guitar tuning, which made it easier for guitarists to play bouzouki, even as it angered purists. However it allowed for greater virtuosity
How many angels can dance on the head of a pin? about how many could perch at the same time on the head of a pin"". Dorothy L. Sayers argued that the question was "simply a debating exercise" and that the answer "usually adjudged correct" was stated as, "Angels are pure intelligences, not material, but limited, so that they have location in space, but not extension." Sayers compares the question to that of how many people's thoughts can be concentrated upon a particular pin at the same time. She concludes that infinitely many angels can be located on the head of a pin, since they do not occupy any space there: