2022-03-13: On logical connectives                           rak
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I was recently travelling by train and the following
announcement was played on repeat it the train station. I was
surprised that this text made it past VIA Rail's legal team,
whom I would have expected to be quite particular about the use
of logical connectives:

> We are doing our part to stop the spread of COVID-19 by
> conducting health checks for every passenger travelling with
> us, as required by Transport Canada. You are welcome on board
> if you do not have a fever and cough, or if you do not have a
> fever and breathing difficulties, or if you have not been
> denied boarding on another carrier within the last 14 days for
> a medical reason related to COVID-19, or if you are not
> subject to a provincial or local public health order. Noone
> should board the train when they are feeling ill, as this
> could pose a risk to others. Thank you.

> Nous prenons les mesures nécessaires pour prévenir la
> propagation de la COVID-19 en procédant à l'évaluation de la
> santé de tous les passagers voyageant avec nous, comme l'exige
> Transport Canada. Vous serez les bienvenus à bord si vous
> n'avez pas de fièvre et de toux, ou si vous n'avez pas de
> fièvre et de difficulté respiratoire, ou si on ne vous a pas
> refusé l'embarquement à bord d'un autre transporteur dans les
> 14 derniers jours pour une raison médicale liée à la COVID-19,
> ou finalement si vous n'êtes pas soumis à un ordre de santé
> publique provinciale ou locale. Aucune personne ne devrait
> monter à bord du train lorsqu'elle se sent malade puisque elle
> présente un risque pour les autres. Merci.

VIA Rail clearly intended to use conjunctions instead of
disjunctions throughout. Indeed, they surely meant to say:

> You are welcome aboard if all of:
> 1) you do not have a fever and cough; AND
> 2) you do not have a fever and difficulty breathing; AND
> 3) you have not been denied boarding [...]; AND
> 4) you are not subject to a provincial or local public health
>    order.

instead of:

> You are welcome aboard if any of:
> 1) you do not have a fever and cough; OR
> 2) you do not have a fever and difficulty breathing; OR
> 3) you have not been denied boarding [...]; OR
> 4) you are not subject to a provincial or local public health
>    order.