No one knows, but we are all very grateful!!

Ultimately, mathematics is based on strings of logical propositions that can either be true or false. This parallels the fact that in the physical world we have something called 'cause and effect' where 'A comes before B'. In other words, the fact that we have mathematics is a result of the fact that nature is a logical system in which cause and effect operate to create physical chains of true-false propositions. We create these mathematically, and search for their analogs in nature, so in essence it is a circular process.