Some conversation start with the mention of a desirable or of an undesirable fact. We saw one example with [ex_lunch, p.6], in which the desirable opportunity of having had a Christmas lunch was intended. Here is an example where the topic, the repainting of old doors, is presented as undesirable.
[ex_doors]
context: A is repainting doors in his home, and he decided to remove old paint first, which proves to be a hard work.
A1- Ben moi, j'en bave actuellement parce qu'il faut que je refasse mes portes, la peinture. Alors j'ai décapé à la chaleur. Ca part bien. Mais pas partout. C'est un travail dingue, hein?
[...]
B2- Quelle chaleur? La lampe à souder?
A3- Ouais, avec un truc spécial.
B3- Faut une brosse, dure, une brosse métallique.
A4- Oui, mais j'attaque le bois.
B4- T'attaques le bois.
[pause 5 secondes]
A5- Enfin je sais pas. C'est un boulot dingue, hein? C'est plus de boulot que de racheter une porte, hein?
B5- Oh, c'est pour a qu'il vaut mieux laiss... il vaut mieux simplement poncer, repeindre par dessus
A6- Ben oui, mais si on est les quinzièmes à se dire a
B6- Ah oui.
A7- Y a déjà trois couches de peinture, hein, dessus.
B7- Remarque, si elle tient bien, la peinture, là o elle est écaillée, on peut enduire. De l'enduit à l'eau, ou
A8- Oui, mais l'état de surface est pas joli, quoi, a fait laque, tu sais, a fait vieille porte.
A1- I have to repaint my doors. I've burned off the old paint. It worked OK, but not everywhere. It's really tough work!
[...]
B2- How are you burning them? Are you using a blowtorch?
A3- Yes, with a special thing
B3- You have to use a wire brush
A4- Yes, but that wrecks the wood
B4- It wrecks the wood...
[pause 5 seconds]
A5- It's crazy! It's more trouble than buying a new door.
B5- Maybe you'd do better just sanding and repainting them.
A6- Yes, but if we are the fifteenth ones to think of that
B6- Oh, yeah...
A7- there are already three layers of paint
B7- if the old remaining paint sticks well, you can fill in the peeled spots with filler compound
A8- Yeah, but the surface won't look great. It'll look like an old door.
We can express part of the logical context underlying A1 this way :
repainting_is_tough_work => UND
[old_paint_is_burnt_off & not repainting_is_tough_work] => F
These introductions in the (un)desirable mode bear some resemblance to the improbability case. We may assume that the speakers are able to assign a priori a positive or negative desirability value to each imaginable event. One can even see in this parameter a second dimension of information (see [Dessalles 1993]). For instance, the event "X has been elected" brings only one bit of information in the Shannon sense if the two candidates are more or less equally matched. But it may bear a very high (un)desirability value depending on who you favored, if you feel concerned by the election. We got a third condition for logical relevance :