The first radish harvested from my windowsill is a dumb little thing. Never a thought in its life, as far as I know.
Tom's "talking" gorilla Koko can carry on a conversation of sorts, but I don't don't expect he'll be commenting on Tom's posting.
The difference between me (and you) and Koko and the radish is all in the numbers. A neuron is a stringy sort of cell that goes snap, crackle and pop. There are something like 100 billion neurons in the human brain. A typical neuron has several thousand connections to other neurons, and each connection is capable of a dozen or so activation levels.
The number of possible neural states is staggeringly large: Imagine your brain as a bowl of Rice Krispies with more potential combinations of snap, crackle and pop than there are atoms in the universe.
Just thinking about thinking makes my head hurt.