If you find this sharp, pointy stone attractive, then chances are you do not have a healthy sense of humanity. For your sake, I hope you find it repulsive. While this rock may seem appealing, this appeal is really just an effect of the stone’s façade. In accordance with the fine Japanese practice of rock gardening, described as shibusa, (meaning quiet & refined taste), stones such as the one pictured above are less refined than those that are naturally smoother, or at least are not this shape. (**please note. This specific rock was not actually used to infer a poor sense of humanity, but it’s the closest rock I could find that looks like the diagram of a bad rock in the book Magic Trees and Stones: Secrets of Japanese Gardening. As I am not a cultivated Japanese Gardener, I may be misleading you completely. If so, I apologize). This is not to say that all stones with points and protrusions are inauspicious—in fact it can be quite the opposite. Protrusions are not all bad—though distinguishing between the bad and the good is a technique reserved for experienced gardeners. Protrusions can act as an indication of the direction in which the stone’s spirit moves, and this can serve to be very helpful when attempting to achieve proper balance between different stones. The trick is to choose those stones that have just the right amount of protrusions, while effectively reading what the stone is saying. A stone’s spirit direction can be sensed by careful observation, paying attention to its contours and composure. It is important to recognize the spirit direction to hear what the stone is saying and, and then to be arrange multiple stones so that they relationships with one another. Just as the balance of the push and pull between the ki of the calligrapher and the word is crucial for establishing and maintaining balance, so too is the ki dynamic of stones. The arrangement of stones needs to correspond to their calling and responding to one another. For example, one stone may be winking at another stone, and this calling needs to be made in the direction that the receiving stone is running. Alternatively, stones may have their backs turned to each other, like lovers in a brief quarrel. The essential element here is to create a connection between the stones, so that together they will speak in unity and evoke a sense of harmony for the garden viewer. When this harmony is achieved, one should get the same sense of power and balance that is similar to the experience of written calligraphy or the rhythm of music. 
Harmony of the qi in the rocks enhances the energy flow and adds to the natural component that is inherent to the garden. As even the slightest error in rock positioning can devastate the balance, it is the role of the garden arranger to partake in effective communication with the rock. It is not only the shape of the rock or stone that contributes to its value, but also its cultivation of moss. As moss takes a long time to grow, its presence is an indication of age, and thus mossy rocks are revered. The subtle refinement of a moss-covered stone is described as shibusa, and is understood to be of ultimate beauty.
The focus of the rock in the rock garden is to listen to, understand and contemplate the rocks and stones as a means to cultivate deeper understanding, while showing respect for the rocks and their ki.
To learn about the variety of stone arrangements, their meanings and symbols, check out these books:
Reading Zen in the Rocks: The Japanese Dry Landscape Garden by François Berthier. ISBN 0226044114
-OR-
Magic of Trees and Stones. Saiot & Wada. ISBN 3101916842K
OR if you just want to look at some really cool, old pictures of Japanese rock gardens & you get excited by looking at really old books, check out the Supplement to Landscape Gardening In Japan by Josiah Conder. ISBN 3103048044L.
