My reading of (excerpts of) Hazrat Inayat Khan's Mysticism of Sound and Music

Summary of "Music, XXI. The Healing Power of Music"
Life is health. Its absence is illness. So all illnesses come from one reason: absence of life. Life in its physical form is called "prana" in Sanskrit, which means "the central breath," capable of attracting from space all the different elements, which are necessary for healing. That's why mystics, healers, magnetizers have always had the culture, the science of breath.
By the use of a medicine, a certain vibration, which has the right intensity, is created in the body (to compensate for the element(s) lacking therein) or a certain rhythm (cf. blood circulation) is brought about. So health is a perfect condition of rhythm and tone; therefore, healing is to put oneself into a state of harmony, regulating the body through rhythm and tone.
Music has the power to tune the soul, provided one knows what particular rhythm and tone are needed to help a troubled person. Health of the soul brings health to the physical body (the opposite isn't always true, thus the limits of the material science of medicine) since often the cause of illness is within: what brings illness is the thought of it rather than illness itself. If one has prepared his heart with love and sympathy, which God teaches, one is able to produce music which has the power to exalt the mind and make it rise above the thought of illness, so that the latter is forgotten.

Summary of "Cosmic Language, II. Impressions"
Places, minerals, plants and animals act as "talking records," continually expressing what has been impressed upon them by man throughout history. The voice of these records can be heard if one's intuition is open enough to feel the vibrations they produce, the atmosphere they create. The same goes for man's impressions on other human beings: when two people associate, they both impress feelings on each other, and vibrate the feelings they have received from each other. So they too act just like records, and it is possible for a careful listener to hear these particular melodies.

Quotes from "Cosmic Language, II. Impressions"
"There is a great wisdom in the saying that a person is known by his associates."
"In every person, however wicked, there is a good string somewhere; you must know where to find it."
"The cloud is much smaller compared to the sun, but often it can cover the whole sun from our sight."

Summary of "Cosmic Language, V. The Life of Thought"
Because "God is omniscient, omnipotent, all-pervading, and the Only Being," life is continuous and death is merely a change. Thus once given birth, every "elemental" (a thought, a word, an action, or a feeling) continues to live, just like the resonance of a bell which has been rung (the longevity of the thought depending on the energy the mind has put into it.) Elementals, created by man, turn into huge lives: human intelligence, working mechanically, indeed directs the whole working of nature. So the responsibility of each human being is great since God laid his trust on man to bring about harmony in the world. When one begins to feel this responsibility, the soul is born again and enters the kingdom of God. From then on, one realizes that every moment of one's life is creative and not a second is wasted. Indeed, if an elemental is sent out only to be spiritualized at first, it will ultimately materialize once the time and conditions are right.

Hazrat Inayat Khan, The Mysticism of Sound and Music, Shambhala Dragon Editions

My reading of Plato's Symposium

Eros' (Love's) role is to transform one's aspiration, one's attraction towards the "beautiful" and the "good" into perpetual possession through procreation (relating to both body and soul.) He achieves this transformation by inspiring one to contemplate the intelligible and the beautiful. This contemplation (assimilated to "birth giving divinities") in turns gives birth to beautiful speeches about knowledge and virtue (philosophy), nice verses (poetry), etc... Indeed, education is no longer seen as the acquisition of a skill relative to sensible, material things, but rather as a conversion: the teacher helps the student to look at the world of ideas (made up of "intelligible forms" which are considered to be the real truth) as a model of which sensible things are merely images. So finally, procreation gives access to immortality on two levels: on the species level (related to the body) and on the individual level (related to the soul.)

SENECA LVCILIO SVO SALVTEM

Here is what I remember (and try to apply to my daily life) from the few Moral letters to Lucilius (written by Seneca) I studied in high school:

1. About friendship: you should be able to say anything to a true friend. You should talk to a true friend in the same way as you talk to yourself.
2. About knowledge: it is useless to have more books in your library than the ones you are actually able to read and digest.
3. About material things: you should be able to treat dishes made of clay as if they were dishes made of silver, and dishes made of silver as if they were dishes made of clay.

Vale.