Why there are 360 degress in a circle

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Discussion Overview

The discussion centers on the question of why there are 360 degrees in a circle, exploring historical, mathematical, and cultural perspectives. Participants examine the arbitrary nature of this division and its connections to ancient number systems and calendrical concepts.

Discussion Character

  • Exploratory
  • Historical
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that the division of a circle into 360 degrees is arbitrary and historically chosen, with no fundamental reason for this specific number.
  • Others suggest that the choice of 360 may relate to the approximate number of days in a year and the number's many divisors, making it convenient for calculations.
  • A participant notes the connection to the Babylonian base 60 number system, indicating that this may have influenced the use of 360 degrees in geometry and timekeeping.
  • One participant mentions that early beliefs about the year having 360 days contributed to this division, linking it to philosophical ideas about cosmic order and cycles.
  • There is a reference to the complications that arose from the incorrect estimation of the solar year, which has led to various calendrical corrections.

Areas of Agreement / Disagreement

Participants generally agree that the division of a circle into 360 degrees is arbitrary and rooted in historical context, but there are multiple competing views regarding the significance of this choice and its connections to ancient systems.

Contextual Notes

The discussion reflects limitations in understanding the historical and mathematical assumptions underlying the choice of 360 degrees, as well as the implications of ancient beliefs on modern concepts.

Harmony360
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Mentor comment: Harmony360 original post violated our rules. The new wording is mine. D H[/color]

So, why there are 360 degress in a circle?
 
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It was arbitrarily chosen.

Well, of course, there was historic reasons as to why it was done, but there is no fundamental reason to use 360 degrees.
 
There are 360 degrees in a circle for historical reasons. It's entirely arbitrary. You could use any number at all. You could say there are 2pi radians in a circle and everything would work out the same. Perhaps 360 was chosen because it's more or less the number of days in the year, and 360 has a lot of divisors.

I didn't follow the details of your chart, but it looks like some kind of cranky mysticism. There is no fundamental reason for dividing a circle into 360 parts, any more than there's anything meaningful about there being 12 inches in a foot.
 
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SteveL27 said:
There are 360 degrees in a circle for historical reasons. It's entirely arbitrary. You could use any number at all. You could say there are 2pi radians in a circle and everything would work out the same. Perhaps 360 was chosen because it's more or less the number of days in the year, and 360 has a lot of divisors.

I didn't follow the details of your chart, but it looks like some kind of cranky mysticism. There is no fundamental reason for dividing a circle into 360 parts, any more than there's anything meaningful than saying there are 12 inches in a foot.

Doesn't it have something to do with Base 60? Much like themetric system is based on decimals?
 
Hey Harmony360 and welcome to the forums.

You might get hints by studying the Babylonians. They used a base 60 number system by default and this might be a connection to the use of 360 degrees for use with time.

They certainly used it for time (this is where we get minutes and seconds from), so its possible that they used it in an extended way for geometry as well.
 
yes, blame the babylonians (i always do).

for a time, it was thought that the year had 360 days in it, which would make 12 months of 30 days each. note that 12 is 1/5 of 60, and 30 is 1/2 of 60, so these are "convenient" fractions in a base-60 number system.

alas, it took astronomers some time to realize that this estimation of a solar year was incorrect. we have been paying for it with various calendrical "corrections" ever since (with bizarre conventions of leap years, and mis-matched month lengths, not to mention the whole gregorian/julian snafu).

apparently, early philosophy literally thought that life was circles within circles, with everything lining up like some grand cosmic clock. the gods themselves created this order, and although such a notion may seem on the surface ludicrous, it persists in many of the common elements of language and thought (including, ironically, a great deal of relatively "modern" science).

early astronomers also thought that the lunar cycle and the solar cycle were synchronized (a quaint reminder of this is still evident on many old clock dials, and even some wrist-watches), which is how subdivisions of solar years came to be called "moons" (months).

which goes to show that an idea, even if totally wrong, may well outlive its usefulness, causing hair-pulling for young geometry students everywhere.
 

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