Seven weights, each the double of the one before. Seven tones for each of the major and minor scales: respectively, do re mi fa so la ti and la ti do re mi fa so – and indeed any of the other heptatonic scales (dorian, mixolydian, ect.). And let’s not forget the seven days of the week.
Precision down to a quarter of an ounce, ‘¼ oz’ tiniest weight, which perhaps explains why sachets of instant yeast come in seven-gram packs, = approximately one ounce.
If you’re old enough to remember being taught imperial measurement at school, do you think it was helpful in understanding and improving maths skills? Do you have any other thoughts on the mysticism of numbers, in particular the number seven? Could it have something to do with the origin of the expression seventh heaven? Let me know in the comments.