When I was a kid the pilgrims and the good ship Mayflower and the turkey were all symbols of Thanksgiving but I remember that the main symbol was a "Cornucopia" or "Horn of Plenty". In Spanish it is called a "Cuerno de la Abundancia". There are various legends about its origin but the main theme seems to center around Greek mythology. When the god Zeus was a baby he had to be protected from his father, Kronus, who had deposed his own father Uranus and feared being deposed in turn by his own son Zeus even though Zeus was still a baby. Kronus's sister Rhea hid the baby Zeus in a cave on Mount Ida on the island of Crete. He was cared for by a number of divine attendants, including the goddess of nourishment, Amalthea, who had the form of a goat and who fed baby Zeus with her milk. The baby Zeus was very strong and while playing with Amalthea he accidentally broke off one of her horns, which then had the divine power to provide unending nourishment, as Amalthea had provided to baby Zeus.
I find the counucopia appealing because I am "cornucopian" who believes that in addition to the continued progress and discoveries of mankind there is enough matter and energy on the Earth (by the grace of God) to provide for the Earth's population well into the future.
In the meantime I think it is fitting to pause and give thanks on this day just for being alive and for being part of this great puzzle. To those of you who can afford to celebrate Thanksgiving as well as those who find themselves in less than a thankful mood or in a difficult circumstance or environment, I salute you all in spirit and the hope for a brighter future for all of us.