The fool....Major Arcana Lession 1. Card 1

Here we see the Fool as a naive young man carelessly looking at the sky to his peril, it immediately brings to mind the old adage of "For fools rush in where angels fear to tread", or to some degree"ignorance is bliss". So firstly we see the Fool carelessly careening toward a cliff top completely oblivious to his peril and this ignorance turns out to be his blessing.
when we see the fool in a spread we find ourselves at the start of any new journey or undertaking this brings to mind the novice of any guild and the first step of any undertaking. The Ryder Waite Deck Defines it as: Let go of expectations and trust your instincts. A person driven by base needs and urges, who has fallen into a state of poverty and deprivation.

So when this is seen in a spread think new beginnings, renewals, and inception. When seen with the Chariot Card and the Ace of Wands implies impending travel for good or for ill is known by those cards that surround these.

Path of Aleph in the Tree of Life Pisces going to Aries, on the other hand Uranus/Mercury standing for curiosity, spontaneity, madness
Element: the Air
Tree of life: Kether going to Chokmah
Element: Air
Number: 0 as nothing and begin of it all

The Fool is the symbol of true innocence, a perfect state of joy and freedom, the sure feeling to be one with the spirit of life, at any time.

The Fool has the number 0, for someone ready to go in any direction, open to all possibilities. He belongs nowhere, has no past, but an infinite future. Every moment is a new beginning. In Arabic letters the 0 has the shape of an egg, the symbol for the origin of life. The Fool is change, motion and the readiness to jump into life, with no cares ever. The Fool knows no difference between possibility and reality, the zero means a total lack of hope and fear, the Fool suspects and plans nothing. He reacts directly to the current situation, nothing is calculated, nothing is hidden.

In most decks the Fool is shown with an animal, as a symbol of nature, the animal soul in perfect harmony with the spirit that just follows its instincts. The Fool is courage, optimism and the belief in life and himself. When times are hard, and we suffer the pressure of 'being reasonable' or denying our instincts, the Fool reminds us that our inner person knows best what to do. 'Always trust your instincts'...

In its negative aspect, the card can say that its qualities are blocked or reversed. Irresponsibility, mad projects, recklessness - the careless human who covers himself with some artificial madness, for distrusting his instincts and fearing standstill and silence.

Drive: Changes, movement, the innocence of a child

Light: The positive break up of structures and limitations, selfless idealism, endless fantasy, optimism, trust to instincts

Shadow: The negative loss of structures, responsivelessness, useless daydreaming, infantility

http://www.corax.com/tarot/cards/index.html?fool