First, the cardinality of its terbri is currently six. Typically, non-joke
gismu are at-most-5-ary, or are arbitrary-ary. Thus, this word is
Second, "delta" in English and technical usage has many usages. The most
common or generally useful such - in my current, subjective estimation - is
either this one or the following:
"x_1 (value) is the difference or change in a function between values x_2
and x_3 in that order (x_2 - x_3)."
We could possibly specify what the function is or the other conditions
under which the change took place. But the primary point here is that the
relevantly changing independent variable in question is not explicitly
specified and the changing values (labelled "x_2" and "x_3" in this
alternative definition) are instances of the function and not of the
variable, unlike the definition supplied in the actual entry.
In other words, one would say, for example, "my profit today from shoe
sales" and "my profit yesterday from shoe sales" in the context of the
alternative definition. In the actual entry'a definition, one would specify
(in the same example) that the function is my profot from shoe sale, the
variable is time, and one is measuring the change in the function as the
variable changes to today from yesterday.
This alternative definition allows for a bit more flexibility than that of
the actual entry. For example, disparate quantities of the same rough type
or dimensions, which could be hard to group/categorize/specify in one
function name, can be easily compared. For example, one could measure the
difference between employee wages and the value which they add to their
employer via sales revenue. These are specific types of monetary value that
the employee 'provides' (one being negative and one being positive for each
the employer and the employee (but it changes depending on the subject));
however, the employee may provide other monetary value to the employer (or
the world at large), so it is hard to name exactly what types of values are
being considered and mutually compared here (id est: what the name of the
On the other hand, the current definition, while perhaps slightly more
clunky, has its own uses and is more explicit and clear when the uses of
each definition option overlap. Additionally, the alternative definition is
perhaps too close to other words in Lojban which mean "change" or
"difference" (in various senses) and, so, can just be rolled up into those.
I see no way by which to reconcile these differences, even if we add sumti
slots to the alternative definition as considered. Fundamentally, one
mentions f(t_i)'s and one simply mentions f and t_i's.