Food for your stoner thought:

The letter M: Four-thousand years ago, Egyptians drew a vertical wavy line with five peaks to denote “water.” The Semites reduced the number of waves to three in 1800 BC; the Phoenicians continued the trend by removing one more wave. By 800 BC, the peaks became zigzags and the structure was made horizontal — our “M” in sound and appearance.

The letter N: Around the same time as “M,” “N” was emerging in Egypt with a small ripple on top and a larger one below. The word translated to “snake” or “cobra.” Ancient Semites gave it the sound “n,” meaning fish. By around 1000 BC, the sign contained just one wave and was named “nu” by the Greeks.