Citation needed: Satoshi's reason for blocksize limit implementation.

I'm currently editing the blocksize limit debate wiki article and I wanted to find a citation regarding the official reason as to why the blocksize limit was implemented.

I have found the original commit by satoshi but it does not contain an explanation. Also, the release notes for the related bitcoin version also do not contain an explanation. I also have not found any other posts from satoshi about the blocksize limit other than along the lines of "we can increase it later".

I'm wondering, was there a bitcoin-dev IRC chat before 07/15/2010 and was it maybe communicated there? The mailing list also only started sometime in 2011 it seems.