It is time to revive grammatical concepts acquired in secondary school. One recognises a main clause because it stands alone. A subordinate clause does not stand alone: to be understood, it needs the main clause. The following sentence has two clauses (each with subject and verb).
Learning needs to be semisupervised←main clause
because variation within each class is large.←subordinate clause Learning needs to be semisupervised because of the large number of
variations within each class. ←no subordinate, one subject and
verb only
The next two sentences do not have subordinates. Their clauses are linked by the “but” conjunction of coordination. Which sentence seems more favourable to the evolutionary algorithms, (1) or (2)?
(1) Evolutionary Algorithms are sufficiently complex to act as robust and adaptive search techniques; however, they are simplistic from a biologist’s point of view.
(2) “Evolutionary Algorithms are simplistic from a biologist’s point of view, but they are sufficiently complex to act as robust and adaptive search techniques.”a
Most of you find that sentence 2 is more favourable. The accumulation of favourable adjectives at the end of the sentence is convincing: “suf- ficiently complex”, “robust”, “adaptive”. Sentence 1 seems to put evo- lutionary algorithms in a mediocre light: the clause at the end of the sentence labels the algorithms with a pejorative adjective, “simplistic”.
It would therefore seem that what ends a sentence influences your judgement more than what starts it. The end of a sentence is not the only influential factor. In a complex sentence composed of a main clause and several subordinate clauses, the main clause is also main in the mind of the reader. Placed in a subordinate clause, informa- tion seems secondary, of lesser interest. Which sentence seems more favourable to the algorithms, (3) or (4)?
(3) Although Evolutionary Algorithms are sufficiently complex to act as robust and adaptive search techniques, they are simplistic from a biologist’s point of view.
(4) Evolutionary Algorithms are simplistic from a biologist’s point of view, although they are sufficiently complex to act as robust and adaptive search techniques.
In sentences 3 and 4, two phenomena combine their strength: the placement at the end of the sentence, and the position of the main clause in the sentence. It is highly probable that, in (3), you view the algorithms negatively; whereas in (4), you may hesitate to make a choice. When the main clause loses its position at the end of a
aReprinted with permission from Sinclair M, PhD thesis, “Evolutionary algorithms for optical network design: a genetic-algorithm/heuristic hybrid approach”, 2001.
sentence, it also loses its convincing power. In (4), the two influential factors are on opposite sides of the sentence (main clause at the head of the sentence and subordinate at the end of the sentence), so they neutralise one another. The reader will then decide according to personal preferences. The biologist will find them simplistic; and the computer programmer, sufficiently complex.
The following table (☛1) is indeed revealing. Thirty-three sci- entists were asked how they viewed the algorithms after reading the four sentences, as indicated in the last three columns of the table. Note the role of the two main factors.
☛1. Influence on readers of information either contained in main clause or placed at end of sentence.
Sent. start Sent. end Main Sub. Neg. Equal Pos.
Sentence 1 Pos. Neg. Pos./Neg. – 15 14 4
Sentence 2 Neg. Pos. Neg./Pos. – 3 4 26
Sentence 3 Pos. Neg. Neg. Pos. 22 9 2
Sentence 4 Neg. Pos. Neg. Pos. 12 19 2
Sent.: sentence; sub.: subordinate; pos.: positive; neg.: negative.
It is interesting to observe how language influences the way you interpret these sentences. If your original language is strongly influ- enced by Sanskrit or Pali, what others consider negative is positive to you, and vice versa. Your choices simply confirm the role of grammar in the way you analyse a sentence. Be aware that if you let your foreign grammar influence the way you write English, it may confuse the English-speaking readers as well as the Chinese and the Europeans.
Unscientific bias All four sentences [(1), (2), (3), and (4)] present identical facts: the algorithms are simplistic from one point of view, (Continued)
(Continued) and they are sufficiently complex from another point of view. If you agree with one point of view (for example, if you find them simplistic), then all sentences 1 through 4 should carry the same message and be equally perceived, whatever the order of the words in the sentence. Yet, this is not the case, is it? You find some sentences favourable and others unfavourable. As you can see, the placement of words in a sentence is not neutral. It has a great influence on the way you perceive the facts presented.
Consider starting sentences with a subordinate clause in order to end them on a convincing main clause. The following sentence starts not only follow this principle, but they also make excellent attention- getters, they really shine at setting expectations, and they are fast to read. If… Since… Given that… When… Although… Because… Instead of… While…
Because the reader is familiar with a template-like grammatical struc- ture (if … then, because … then), reading is faster.