Incommensurable magnitudes

Incommensurable magnitudes refer to two things that are different sizes and they cannot be measured by the same unit. For example, if you have a pencil and a table, they are very different sizes and cannot be measured with the same tool or unit. You can measure the length of the pencil in inches or centimeters, but you cannot measure the size of the table in the same way because it is much bigger. This means that they are incommensurable magnitudes. It's like trying to compare apples and oranges – they come in different sizes, so you cannot use the same measuring stick for both.