I have gathered some quotes from various traditional Catholic sources concerning true chivalry. I hope it is helpful for those reading who are of good will. Out of charity I feel the need to make this post.
To clarify for the women here who are unduly disturbed, Bishop Williamson in the conference given at the beginning of this thread is not stating that it is a sin in itself for women to go out in public alone, but that true Catholic chivalry demands that a woman be accompanied by a man in public whenever possible, and that it is essentially a mark of decay in a society when this does not happen.
Of course, there are exceptions, and one does not need to enumerate them all. It is simply a standard of politeness and courtesy that ought to be observed for the proper protection and honour of women in society. This is the natural consequence of Catholic morality, which elevated women above the state of slavery, this state being customary in the pagan world before Christ.
For further reading on Catholic civilization and practice, see Rev. J. Balmes' work
European Civilization: Protestantism and Catholicity compared. He was a Spanish and Jesuit philosopher, theologian, Catholic apologist, sociologist and political writer,
and the book was published in 1855.
https://archive.org/details/EuropeanCivilisation/page/n9/mode/2upAs a side note, not everything is about only avoiding sin, but also doing what is most pleasing to God in all things. This attitude of seeking only to avoid offence is not in conformity with the spirit of the saints, or with anyone who truly loves another ardently, including God.
And if people think I or others on here sound too much like priests, you are unacquainted with how both laymen and laywomen used to converse with one another, and the laws of Christian charity and truth that are supposed to govern these conversations. All I am doing is repeating what priests have written or said.
The Polite Pupil, for the use of Catholic Parochial and High Schools, by the Brothers of Mary, 1905, p. 11A polite son will act towards his mother with more civility and gentleness than he would towards any other person. He will remove his hat when he is in the same room with her, or when meeting her in public. A polite child will open the door and allow her to pass through first, will pick up any article she may have dropped, give her the best side of the walk, and help her in or out of a car or carriage; will accompany her to the store or the market, will carry a parcel, and will wait upon her anywhere. The Mirror of True Womanhood: A Book of Instruction for Women in the World, 1886, p. 276, example given of public chivalry of a young man with an elderly womanWe once saw in one of the public conveyances of Paris a young nobleman, a foremost member of the Society of St. Vincent de Paul, get out of his place to help a poor infirm old market woman into the omnibus. She was cuмbered with a large parcel, which he took from her, raising his hat to her as if she were a duchess, and then gracefully and gently helping her to a seat. As we passed the market in which she worked, he got out before her, holding her parcel with one hand and giving her the other to assist her to alight; and then, taking off his hat, he kissed her hand to the no small astonishment of more than one of the passengers. She was only one of the many that he was in the habit of visiting weekly to distribute alms and spiritual comfort in the name of the Society. We did not venture to question this noble Christian youth about this demonstration of reverence to one beneath him. But a friend who knew him well said that he had been taught to reverence his own mother in every person of her sex, in the aged particularly, and to that he added the veneration which Christian piety inspires for all who are the recipients of our charity.In such Christian families as his the familiarity which exists between brother and sisters is always accompanied with that feeling of profound respect for the weaker sex, of that invariable deference and courtesy which will keep a well-bred brother always on the watch to help or serve his sister in every thing, — even though no stranger or any other member of the family happen to be present. He is taught to be devoted to his sisters wherever they are, at home or abroad. And one who has that true reverential feeling toward his mother and sisters, cannot help extending it to every member of their sex as long as he lives.The Father of the Little Flower by Céline Martin, 1955It is sufficient to read my mother's letters to realize how much my father had at heart the desire to help her in all her anxieties, whether it was to set out at four o'clock in the morning to find a wet-nurse for a sick baby, or on another occasion to accompany her a distance of six miles from Alençon on a freezing cold night to the cradle of her dying little Joseph. — p. 41Our father aided as much as he could the development of the spiritual life. Thus several times he accompanied Marie to see her Spiritual Director, Father Pichon. — p. 47At that time the school-children were never allowed to go alone, and young girls of our environment were always accompanied. Truly it was servitude. Every morning someone had to go with us and call for us in the evening, for we were half-boarding pupils. Sometimes it was the maid, but often Papa was asked to take his turn. He did it willingly, but nevertheless one could see that it was through virtue. — p. 50Louis Martin to his daughter Pauline: "I have allowed you to go to Carmel for your greater happiness; however, do not imagine that it will not cost me a sacrifice, for I love you very much." He accompanied her himself to the Monastery on the following October 2nd, and led her to the Altar for her Clothing Day on April 6th, 1883. — p. 59...and our father accompanied her [his daughter Marie] to Brittany that she might make a retreat preached by the saintly Jesuit there. — p. 61