“Able was I ere, I saw Elba.” - Napolean

Poetic as it may sound, “able was I ere” is not a sentence we may normally use, even if we forgive the archaism of the expression. When you introduce yourself to someone, it is customary to say ”My name is Thomas” rather than “Thomas is my name”. Grammatically speaking, there is nothing in particular that forbids you to say that. The verb ‘to be’ is a so-called copular verb, which means that it acts like an equal sign, signifying that the two nouns or adjectives surrounding it are equal (or at least that is the simplistic view). For an equal sign, then, which one of the two arguments comes first should not be a matter of concern, because they are, after all, equal. But we know that is not true.

Let us start examining this issue by first considering under what circumstances we might use the sentences:

  1. My name is Thomas.
  2. Thomas is my name.

As we mentioned above, sentence 1 is used when we first introduce ourselves, when we first meet someone who does not know anything about us, not our name at least.

A: What is your name?
B: My name is Thomas.

Sentence 2, on the other hand, may be used when someone has mentioned the name/word ‘Thomas’, but does not know whose name it is or what it is. Consider the following situations:

C: Whose name is Thomas?
D: Thomas is my name.

E: What is this word written here? ‘Akwasi’?
F: Akwasi is my name.

Portia: Is your name Shylock?
Shylock: Shylock is my name.

- Shakespeare, The Merchant of Venice

In summary, for sentence 1, “Thomas” is unknown to the listener, or in other words, it is a piece of new information to the listener; while for sentence 2, “Thomas” (or “Akwasi”) is a piece of old information, and instead, “my name” is the piece of new information.

In natural languages, English included, there is a tendency to place the old information in the beginning of a sentence, and the new information towards the end.

Technically, we can identify a topic and a focus in basically every statement.

A topic sets the context or the scope of a sentence, it tells the listener what this sentence is about. A topic can be specified using phrases like “as for…”, “as far as … is concerned”, “concerning …”, but they can also be present without the use of any such devices. When I say “My name is Thomas,” for instance, “my name” is the topic I want to talk about. It can be rephrased or understood as “as far as my name is concerned, it is Thomas.” Because of its function, the topic must be a piece of old information that the listener knows about or understands.

A focus, on the other hand, is the main message or information the speaker wishes to convey to the listener. Because of its nature, it is usually a piece of new information to the listener. “Thomas” in “My name is Thomas” is therefore the focus of the sentence.

So it explains why normally it does not sound right to say “Thomas is my name” when you first introduce yourself. We can now also understand the weirdness of “Impossible is nothing” (although it certainly sounds better once you have got used to it). For the latter case, the sentence word order is reserved to emphasize “nothing”. Similarly Napolean’s quote is constructed that way to place the focus on “ere”, creating a contrast between “ere” and “now”.

A legitimate question to ask at this point is why our languages have these properties. A probable answer is that when we communicate, we need to first give the listener a signal of what we are going to talk about, catch their attention and get them prepared, and leave the most important information at the end so that the listener has sufficient time to process the message.