The Pie Chart and levels of consciousness

I have been through a succession of stages of understanding and enlightenment in respect of the pie chart. These can be seen as a progression through levels of consciousness (how pretentious does that sound?). Anybody for whom a discussion of pie charts would quickly lead to a state of unconsciousness,  stop reading now - save this for your next bought of insomnia

First Level
I realised that the name referred to pie the food not to pi the strange number with lots of decimal places. Maybe I was unique in mistakenly assuming that the name had something to do with the properties of a circle.

Second  Level

I realised that pie charts were a pain to draw. I was brought up in the Lower Palaeolithic, before the advent of spreadsheets. At school, drawing pie charts involved compasses (to draw circles) and protractors (to measure out angles). When I worked as a professional illustrator, I had to do all this but also very neatly and using ink.  Differentiating the different slices involved very carefully ruled hatching, precise stipple,  or sticking on pieces of expensive patterned film ("Letratone") cut precisely. In those days a spreadsheet was a major undertaking. You had to be really sure you wanted one.

Third  Level
Spreadsheets. Along came Loutus 1-2-3 and then Excel. I was delighted to find that Excel can produce very quickly. Not only that, it offered aesthetically pleasing variations such  as 3D and "exploding pie". I felt very grateful for the existence of computers. I recreated Manhatten using 3 D column charts.

Fourth Level
Having read the works of the data visualisation gurus - I realised, with a bit of an embarrassed sinking feeling, that I was supposed to deprecate pie charts. I realised that the exploding 3D charts made me look like a novice rather than an expert. I stopped using pie charts immediately. I scoffed at other people who still used pie charts and I felt superior.

Fifth Level
I realised that the pie chart can be good after all - if used in the right way. I felt stupid for not holding onto this when I jumped smugly to Level  Four.

Sixth Level
It's a pie chart...but not as we know it. I then realised that there are other kinds of charts which look like pie chart but are really something else. I could not see any missiles directed at these from the data visulaistaion gurus, so concluded that they may be safe to use


Seventh Level
Is there a seventh level or beyond? I have not got there yet. I will let you know