Iverson explained the reasoning behind this in an appendix to a book he wrote in the 60's: http://www.jsoftware.com/papers/EvalOrder.htm http://www.jsoftware.co

Iverson explained the reasoning behind this in an appendix to a book he wrote in the 60's: http://www.jsoftware.com/papers/EvalOrder.htm http://www.jsoftware.com/papers/EvalOrder.htm It's the approach used in APL and J, and I've certainly found it far preferable to the current math notation standard.