We use the same language but do we understand each other?

Q. I get the impression sometimes that communication/language between people is a hit and miss affair and could go very wrong. We all use the same words and assume that we share and understand the meaning in the same way, that we actually understand each other. Is this correct to assume?

A. It is not an assumption it is part of what it is to be a language user. Of course there are failures to communicate: speakers understand words in different ways and assume their understandings are the same. But could this always be the case? Surely not. To understand an expression I need to be able to use it correctly. Can I tell if my own use is correct or not? Well no: because whatever seems right to me will simply count as right and that just means that I go along using a word as I feel. So a condition on measuring the use of a word against a standard of correctness is that other speakers can check on whether that use is or isn’t correct. So, if there’s to be a language at all, speakers must be able to check on one another’s use, they must be able to communicate. (My thanks to Ludwig Wittgenstein for this insight.)   Professor Bernhard Weiss, Dept of Philosophy University of Cape Town.