Egg

The Egg is a universal symbol representing a primordial source from which some primordial being comes into existence. In Theosophical literature there are several Eggs, according to the plane we are talking about. H. P. Blavatsky explained:

Thus the Egg, on whatever plane you speak of, means the ever-existing undifferentiated matter which strictly is not matter at all, but, as we call it, the Atoms. Matter is destructible in form while the Atoms are absolutely indestructible, being the quintessence of Substances. And here, I mean by “atoms” the primordial divine Units, not the “atoms” of modern Science.

Eternal egg

In the first volume of The Secret Doctrine, H. P. Blavatsky explained:

The eternal egg is a pre-differentiation in a laya or zero condition; thus, before differentiation it can have neither attributes nor qualities.

In Stanza II.3 the word "matri-padma" (from mātṛ, "mother" and padma, "lotus") is used. According to Blavatsky this refers to the eternal egg:

Q. Is the Matri-Padma the eternal or the periodical Egg?
A. The eternal Egg; it will become periodical only when the ray from the first Logos shall have flashed from the latent Germ in the Matri-Padma which is the Egg, the Womb of the Universe which is to be.

Virgin egg

According to Mme. Blavatsky "The 'virgin egg' is already qualified and therefore differentiated" This Egg corresponds, at the level of the solar system, with what at a universal level is called chaos:

The “Virgin Egg” is the microcosmic symbol of the macrocosmic prototype—the “Virgin Mother”—Chaos or the Primeval Deep.

The Virgin-egg being in one sense abstract Egg-ness, or the power of becoming developed through fecundation, is eternal and for ever the same. And just as the fecundation of an egg takes place before it is dropped; so the non-eternal periodical germ which becomes later in symbolism the mundane egg, contains in itself, when it emerges from the said symbol, “the promise and potency” of all the Universe.

Mundane egg

Also known as the "World Egg", is the virgin egg once it has been impregnated by the "ray" from the Logos:

The Mundane Egg is simply the first stage of manifestation, undifferentiated primordial matter, in which the vital creative Germ receives its first spiritual impulse; Potentiality becomes Potency.

The "germ" fecundated by the ray is sometimes referred to as "the point in the mundane egg." This point is the Second Logos which, after being incubated, emerges as the Third Logos or the manifested creator:

Appearing with every Manvantara as Narâyan, or Swayambhuva (the Self-Existent), and penetrating into the Mundane Egg, it emerges from it at the end of the divine incubation as Brahmâ or Prajâpati, a progenitor of the future Universe into which he expands.

In Hindu philosophy the mundane egg is called Hiraṇyagarbha, meaning "golden womb" or "golden egg".

The Germ

Related to the idea of the Egg is that of the "Germ":

The “Germ” is a figurative expression; the germ is everywhere, even as the circle whose circumference is nowhere and whose centre is everywhere. It therefore means all germs, that is to say, unmanifested nature.

The Germ is eternal, the undifferentiated atoms of future matter—is one with space, as infinite as it is indestructible, and as eternal as space itself.

Having flashed out from this central point and thrilled through the Germ, the Ray is withdrawn again within this point and the Germ develops into the Second Logos, the triangle within the Mundane Egg.

The “Germ”—the point in the Mundane Egg, represented by matter in its abstract sense. But the term “Point” must not be understood as applying to any particular point in Space, for a germ exists in the centre of every atom, and these collectively form “the Germ;” or rather, as no atom can be made visible to our physical eye, the collectivity of these (if the term can be applied to something which is boundless and infinite) forms the noumenon of eternal and indestructible matter.

Further reading

• Egg at Theosopedia