the reason why Romans sometimes still use number four as IIII instead of IV

In the Roman numeral system, numbers are represented using letters from the Latin alphabet. The basic symbols for Roman numerals are:

• I: 1
• V: 5
• X: 10
• L: 50
• C: 100
• D: 500
• M: 1000

In this system, symbols are combined to represent numbers. The general rule is that smaller numbers are written before larger numbers to indicate addition, and subtractive combinations are used when smaller numbers appear before larger ones.

The number "4" is written as "IV" in Roman numerals because the "V" (5) is subtracted from a higher value "I" (1). This might seem counterintuitive since we would not write "4" as "1+1+1+1" in Arabic numerals. But in Roman numerals, the combination of "I" placed before "V" implies 5 - 1, which equals 4.

The reason "IIII" was sometimes used for "4" is historical and cultural, rather than mathematical. Here are some reasons why "IIII" might have been used:

1. Lack of Standardization: In the early use of Roman numerals, there might not have been a strict standardization, leading to variations in how numbers were represented.

2. Aesthetic Reasons: Some people might have preferred the symmetry or visual appeal of "IIII" over "IV."

3. Misunderstanding: Some individuals might not have understood the rules of Roman numerals and simply added the value of "I" four times to get "IIII."

4. Mimetic Writing: Similar to the aesthetic considerations, some might have used "IIII" to mimic the appearance of the number "4" in cursive writing.

It's worth noting that "IV" is the correct and standard form for representing the number four in Roman numerals, and "IIII" is considered incorrect or archaic. However, the legacy of "IIII" can still be seen in some historical documents or decorative uses where it was used without strict adherence to the rules of Roman numerals.