Learn English – Is the letter “c” always silent in words which have the letters “sc”

There are several reasons, three of which stand out:

1. If you keep the original spelling, connections with the same word used in other languages remain intact. In honest and psychology, for example, this makes it easier for people to communicate across English, French, Latin, Greek, etc. In German, they spell Zentrum. This makes it harder for us to remember how it is spelled, and sometimes this even makes it harder to learn the word for learners. Similarly, Dutch spells akkoord, which is again less consistent with many other languages and the language of origin, French.

2. It is terribly hard to get people to change the way they have always spelled words. Imagine if you had to change your spelling all of a sudden after having spelled a certain word the same way for 30 years! Or, what may be even worse, regular spelling changes occurring every 5 years, which nobody will be able to learn or keep up with, as in Dutch. And, even if you decide that something needs to change, there will be 1001 opinions as to how. Should it be onest? onnest? onnist? As it is, no spelling system in the world is wholly phonetic, not even new systems. Imagine you had to read a teks laik this, weh ai'uhv tsyowsin suhtin konvensyuhns.

3. How will you take into the account the fact that people in different regions pronounce the same word differently? Should all spelling be based on the phonetics of Received Pronunciation? Or should each region use its own spelling, making, say, British harder to read for Australians and vice versa?

In the general case, it is impossible to know for certain the mapping between graphical units — letters — and sounds in the English language. That is simply the way it is.

In the specific case, there is no English word that starts with /ts/ or /gn/, because that sequence cannot occur in that position in English. Therefore the first letter of each of those two pairs is always silent.

There are enough of these specific cases that a given native speaker stands an excellent chance of guessing the same pronunciation as some other native speaker will guess. And therefore this indeed a system to it all.

It just takes a very long time to learn if you are not born to it.