@Cycloptichorn,
Not sure I agree with you...
The idea of 1 and the idea of 2 are much older than the idea of zero.
Most Ancient civilization, such as the Greeks and Romans, understood 1 and 2 very well... but had no way of representing, or understanding, "zero" as a number". Some cultures used a "zero" as a placeholder... but not as a number (i.e. they didn't use it in arithmetic).
I personally think 1 is simpler... babies, for example, understand self before they understand the existence of others.
But mathematically speaking... cultures learn how to count positive integers (starting at one) long before they figure out zero. That is not surprising though when you think that positive integers are concrete objects... where as zero is an abstract concept.