Tying rope around a rock and placing it at an entry way is a subtle Japanese shorthand for “Please Do Not Enter.” The Japanese call this tradition a tome ishi (stop stone), or sekimori ishi (boundary-guard stone).

I like this tome ishi image for its gentle spirit. This photo can be used as a polite sign for anyone living in a group setting. Simply hang the photo on your door those times you wish to be left alone!

A tome ishi a “soft barrier” politely telling visitors not to enter an area. You traditionally see a tome ishi in Japanese gardens, especially those with tea houses. They are directional markers, guiding guests past various turn offs and along a prescribed scenic route.

They are used culturally in other settings as well, such as politely informing people a restaurant or a scenic route is closed.

A Japan Times article gives history on this device:

In legend, at least, sekimori ishi are linked to the great tea master Sen no Rikyu (1522-1591). The story, as recorded in a renowned tea tome called the “Nanporoku,” is that Rikyu once invited a famous Zen priest to call. But before the priest arrived, Rikyu placed a little pot in front of the door, wordlessly and playfully challenging his visitor to find a way in without crossing this symbolic barrier…

No one knows whether Rikyu really did this, given that the story was recorded a full century after his death. And no one knows who decided to use a stone instead of a pot. But one way or another, the convention developed in tea circles of marking boundaries with a tied-up stone. Even today, part of the preparation for a tea ceremony is to set out these stones, not only to guide guests to the tea house but also to express the host’s desire to help guests follow the correct spiritual path….

I’m charmed by the concept of a hard object as such a “soft” barrier. If you think about it, a little rock isn’t going to keep out anyone determined to get in. You could step right over it, if you were so inclined. The magic of these rocks is that they work by tacit agreement, an understanding between host and guest….
Stone Path Through a Japanese Garden

From Tome Ishi by Alice Gordenker in the Japan Times

This Tome Ishi gently closes entry to the pathway (left) of the Japanese Garden at the Chicago Botanic Garden.