on the margin
Even I don't really regard this in any significant sense as work on the foundations of mathematics, but what I am going to mention here are the first stirrings of interest in foundational issues which I can remember.

Minsky
Since about 1967 I had been aware from Minsky ([Minsky67]) of the idea of a computable real, and of the distinction between that and the real reals.
In 1972, just before I returned to University to do my first degree in Maths and Philosophy I spent some time ruminating in this area.


Turing, Church, Post
Probably following references from [Minsky67] I obtained copies of seminal papers by Alan Turing, Alonzo Churchand Emil Post relating to computability.
I don't think I actually understood much of the detail.

Reals
I came to the view that the inadequacy of the available implementations of real arithmetic (on computers) was partly attributable to the fact that mathematics had been developed using the classical concept of real number and that it would all have been much better if it had been done with computable numbers.


Constructive Mathematics
By these means, before I knew much more mathematics than I learnt at school, I found myself with constructive inclinations.
I'm not at all sure that I had even heard of constructive or intuitionistic mathematics at that time.
Later I concluded that the problems which concerned me could be remedied within the framework of classical real analysis.

Computing with Reals
My interest, though not a very active one, persists to the present day and gave rise to a few web pages.

