1 + 1 = 2. "The height of certainty," you say. Yet, how rarely we can be sure this is correct, when we consider how often one of something plus one of something equals something other than two of something. How rarely we ask the question, "of what?" when it comes to 1 + 1, which makes all the difference in the world.

So, 1 (of what?) + 1 (of what?) = how many we cannot know, unless we have first answered the first two "of whats" and, further, defined the "of what" that we are counting as our result. For example 1 salt + 1 liquid may = 3 states, or one gas, or some other number of distinct objects.

Only when our conception of number is limited to digits as they appear on a number line, or when our counting is limited to things of the same kind, is 1 + 1 = 2 certain; but that is only because our thought in those instances is constrained to the world of sequential integers. Most of the time, this question about what it is we are counting goes unacknowledged. 1 (integer on a number line) + 1 (integer on a number line) = 2 (integers on a number line), is what we are in effect saying, were we to voice the unspoken--and then we act as if that is the supreme and exhaustive truth about 1 + 1.

In some ways, these instances in which 1 + 1 equals 2 are the least interesting of the 1 + 1 possibilities, and may not even be the most common; yet we mistakenly hold it out as the apex of certain statements. It definitely reveals to us a law of our own consciousness. But, is it fair to hold it forth as the model of truth--or the kind of certainty that all of our statements should aspire to, if we want to consider ourselves reasonable and empirical? Is this fair, when we consider how much of our experience necessarily falls outside of these number-line scenarios?

Outside of the relatively narrow set of conditions in which 1 + 1 unequivocally equals 2, the story of 1 + 1 can be anything other than certain, and can admit as much flexibility as to fill the narrative of a lifetime--such as 1 (man) + 1 (pen) = 16 (books); 1 (character) + 1 (setting) = 1 (novel) or 80,000 (words); or 1 (woman) + 1 (man) = 5 (children), 1 (family), or a host of problems.

Don't even get me started on 2 + 2.