I will make the assumption that MM’s will recognize this as one of the symbols of the third degree. To those who aren’t MM’s, this problem is officially presented to us as an example to teach Masons to be lovers of mathematics. But how is it related to morality? Why this symbol? Our monitors say nothing on the subject. Here’s a possible interpretation by C.C. Hunt.

We are traveling upon the level of time to our eternal destiny. We cannot stand still, but must constantly go forward. Shall we also go upward? All the time there is a spiritual force striving to lift us to higher levels. We may refuse to avail ourselves of it and remain in the depths of our lower nature; or we can accept it and allow its divine influence to shine in our lives. The base represents our earthly nature on the level of time; the perpendicular is the divine spirit striving to manifest itself through us. When these forces are squared to each other, their union becomes a constant onward and upward movement to the throne of God Himself. Pythagoras himself recognized this symbolism when he said that early in life he came to the place where two ways parted. One was easy and pleasant traveling; the other was rugged and tended upward. It necessitated hard climbing. Which was the way that led to life? All who travel there and find these two paths know that he should choose the upward path, but the other seems so much more pleasant, and many are inclined to walk therein. They will try it a little while, and then return to the better way. But there is no turning back on the level of time. The farther they go on the lever level, the wider apart become the two ways, and the harder to cross from one to the other."