"Sohl" has nothing to do with S.O.H.L. Sohl is decent family of bridge conventions, while S.O.H.L. is an acronym for "Slap Ouwe Hoeren in het Luchtledige" (a well known dutch saying, meaning: Amusing Twaddling into Outer Space, transl: "to Slack-Old-Whore into Vacuum").
In bridge bidding however, one could claim:

Sohl is the Soul of MAF
It is a conventional response to all 1-level opening bids and to some higher level opening bids as well.
The word "sohl" has been derived from the well known conventions: Lebensohl, Rubensohl, YAS = "Yet Another Sohl" etc.

Many times Sohl has been a matter of question on this website. You may use the next buttons to have a look around to see the various applications. Everywhere you will be enabled to return here.

1-Sohl 1-Sohl 1©-Sohl 1-Sohl 1NT-Sohl 2©/-Sohl 2NT-Sohl 3NT-Sohl
There are three special Sohls, which have names of their own. The first two are mention in the above row under different names.
Half Sohl   FAKE Sohl   lhoS-Sohl   Simple Soul Sohl   Jumping Ja-cott Sohl
All these conventions have many of the next properties in common:
All Sohl-bids in MAF do have those properties. This explains the origin of the name "SOHL" in MAF.
When the opponent player between opener and responder overcalls, sohl has become impossible. MAF would not be MAF if no counter measures were taken against manoeuvers like that one. Unfortunately I did not succeed in finding the ideal solution for any situation.
If you compare the "multi-way forcing Sohl" convention with the Stayman, Jacoby and Lebensohl conventions, you see something strange:
The Sohl-responses have 3 properties: Summarizing one can claim:
The Sohl-response, which is a Jacoby-like response == "intelligent transfer",
asks for a Sohl-rebid, which is a Stayman-like rebid == "intelligent relay".
As an illustration you could look e.g. to the descriptions of particular applications of this sohl-principle by returning to the top of this chapter.
In the next diagrams the nature of all Sohl agreements after the "one in a suit" - opening bids have been collected in an attempt to create an Sohl-overview.

To my regret this has not yet been accomplished. Half of it is on a spreedsheet which cannot be opened any more by Excel. Due to:

Norton Uninstall
a lot of damage has been brought about in my computer. Many programs do not function any more after cleaning up my registry. A few years ago I had big problems with the Norton Desktop
So Mike Alerts you Folks: never use Norton Windows software
Reinstalling Windows95 and Office97 has worked only partially. I am afraid that I have to reinstall 3GB of software. I don't like the idea.